Stro Fit and Use Guide

This guide explains how to fit and use Stro correctly.

This guide does not replace the Safety & Use Warnings. Read both before using Stro.

Stro is designed for controlled seated use. Correct fit, correct strap position, correct device height, correct tongue position, correct clothing, and gradual use are essential for Stro to sit and function as intended.

Before you start

Use Stro only while seated in a stable position.

Do not use Stro while standing, walking, driving, exercising, lifting items, caring for children, bending forward, wearing bags or other straps, or travelling in a moving vehicle.

For your first week, use short sessions only. If you are unsure, start with around 5 minutes.

Nothing should hurt for Stro to work. If you feel pain, jaw discomfort, tooth pressure, joint irritation, muscle strain, dizziness, numbness, tingling, or unusual symptoms, stop using Stro and check your fit, weight, and session length before continuing.

Step 1: Choose the right seated setup

Stro works best when used in a stable seated position.

1. Active position — best effect
Sit near the edge of a stable chair that does not have wheels. A dining-style chair often works well. Keep your feet grounded and sit upright without leaning back. Choose a chair with a stable seat and an edge that is not too sharp or uncomfortable against your thighs.

2. Upright supported position — second best
Sit further back on the chair, with more of your thighs supported by the seat, but without leaning back on the backrest. This is still an active position, but it is slightly more supported than sitting near the front edge.

3. Rest position — gentlest effect
Sit back on the chair with your hips further back and lean against the backrest. This can be used when you need more support, but the effect may be gentler and less efficient than the first two positions.

Stro can be used while sitting on a wheeled chair, but the effect is generally better on a stable chair without wheels. Take extra care on wheeled chairs, as movement of the chair may affect your stability and positioning.

Step 2: Wear the right top

Stro is intended to be worn underneath clothing.

For best and safest use, wear Stro underneath a fitted top that sits close to the chest and helps cover the device. Ideally, the top should cover the whole device or most of it.

A fitted top with an internal supportive layer, such as an inner crop-style layer or built-in support layer, may help keep Stro close to the body.

The purpose of the fitted top is to help keep the device close to the chest and reduce swinging. If the device detaches or shifts, fitted clothing may also help reduce the speed and distance of movement.

Do not wear Stro loosely over clothing in a way that allows it to swing freely.

Step 3: Place the sleeve on the device

Place the sleeve over the device before use.

The sleeve is intended to improve comfort, reduce direct temperature sensation from the metal body, and help protect the device during normal use.

Step 4: Position the strap correctly

The silicone/grip side of the strap must face your skin.

Place the strap around your neck with the silicone/grip side touching the skin. The strap should sit at the root/base of your neck, as low down on the neck as possible.

The strap should sit flat and wide against the skin, creating a broad, stable loop around the base of the neck.

For best function, the strap needs direct skin contact where it sits above the collarbones. Do not place an undershirt, thick fabric, or other clothing between your skin and the strap in this area.

Make sure:

  • the silicone/grip side faces the skin

  • the strap sits flat and wide against the skin

  • the strap is positioned at the root/base of the neck

  • the strap extends as low and broad as possible around the base of the neck

  • the full width of the strap touches the skin where it sits above the collarbones

  • the strap is not reversed, twisted, folded, or bunched

  • the strap is not sitting over clothing near the neck

  • the device is positioned correctly on the upper chest

  • the device and sleeve are touching the skin directly

  • the device is worn underneath a fitted top

If the strap is reversed, twisted, folded, sitting over clothing, or not fully touching the skin, pause and adjust it before continuing.

Why the strap needs skin contact

The strap is designed to grip directly against the skin at the root/base of the neck. This contact point is part of how Stro is designed to work.

The silicone/grip surface helps the strap stay low and reduces sliding during seated use.

Stro is designed to be fitted to your body in a specific position so the device can create its intended posture-practice effect. If the strap does not grip correctly, the device may sit incorrectly, move too much, or not work as intended.

Do not place the strap over clothing near the neck. Do not use the strap with the silicone/grip side facing away from the skin.

Step 5: Adjust the strap length

Adjust the strap length using the tri-glide buckle so the device sits securely in the correct position.

After adjusting the strap, check that:

  • the strap is still sitting at the root/base of the neck

  • the strap is as low down on the neck as possible

  • the strap is flat, wide, and not twisted

  • the silicone/grip side is touching the skin

  • the device sits securely on the upper chest

  • the device does not feel loose, unstable, or too tight

The strap should feel secure, but it should not feel restrictive.

Step 6: Position the device

After the strap is correctly positioned at the root/base of your neck, check the device position on your upper chest.

As a general guide, the top edge of the device should sit approximately 0–4 cm below your collarbones after the strap has been adjusted correctly.

The device must not sit above your collarbones. It may sit close to the collarbones if that is the correct fitted position for your body, but it should not sit above them.

Always check the device position after the strap has been placed correctly. If the device first appears slightly low on your upper chest, it may move into the correct position once the strap is adjusted fully down to the root/base of the neck. Adjusting the strap to the correct neck position may raise the device slightly.

The placement is important. Stro is designed to guide posture practice from a specific position on the upper body. If the device sits too high, too low, or too loosely, it may affect the wrong areas, reduce the intended effect, or increase the risk of discomfort or strain.

If the strap length is adjusted so the device sits too far down the chest, the device may encourage an unsuitable posture where the chest sits too far forward.

If the device sits too high, including above the collarbones, it may affect the wrong areas of the body and may cause discomfort, strain, or injury.

Different bodies may require slightly different adjustment. Stro may not fit every body type. If you cannot position the device correctly within the recommended area, contact Stro support for fit help before continuing.

Step 7: Choose the right weight

Use the size and weight that is suitable for your body, strength, posture, and current tolerance.

The 450 g version is intended to suit most body types. The 800 g version is intended for users who are larger and stronger.

Do not choose a heavier weight to get faster results. More weight is not always better.

If the device feels too heavy, creates strain, causes discomfort, affects your jaw or teeth, or makes you fatigue quickly, reduce your session length or use a lighter option if available.

Step 8: Check tongue and jaw position

Your tongue should rest comfortably against the upper palate without touching or pushing into the front teeth. Before and during use, check that your tongue is in this position.

If your tongue does not comfortably fit on the upper palate without pressing against your front teeth, use extra caution. You may need to make a conscious effort to keep the tongue resting on the palate without pushing into the front teeth.

Stro may not be suitable for you if you cannot find a comfortable tongue position without tooth pressure, jaw tension, tongue strain, or dental discomfort.

If you have TMJ issues, jaw joint pain, jaw clicking, jaw locking, dental concerns, orthodontic treatment, bite issues, or a history of jaw pain, seek advice from a qualified health professional before using Stro.

Stop using Stro if you notice tooth pressure, jaw tension, tongue strain, bite changes, dental discomfort, or unusual pressure in the mouth, jaw, or face.

Step 9: Check the clips and attachments

Before each use, check that both clips are securely attached.

Also check that:

  • the attachment points are secure

  • the hinge is secure

  • the clips are not cracked, loose, damaged, or unreliable

  • the strap is not worn, torn, stretched, slippery, or damaged

  • the silicone/grip layer is not peeling, worn down, detached, or separating from the fabric

Do not use damaged or faulty parts. Contact Stro support if anything appears damaged, loose, worn, or unreliable.

Step 10: Check strap grip

The strap must grip properly during use.

If the strap is not gripping properly, first check whether it is wet, sweaty, dirty, oily, reversed, or sitting incorrectly.

Remove Stro, dry the strap and your skin, clean the strap if needed, and refit it correctly before trying again.

Replace the strap if the grip surface is worn, damaged, smooth, peeling, separating, or no longer works as intended.

Do not use Stro with a strap that cannot grip securely enough for normal seated use.

Step 11: Use Stro while sitting still

Once Stro is fitted correctly, sit upright in a stable seated position.

The best use case is sitting still because the strap and device position are less likely to shift.

Some upward movement or gliding of the strap may happen during use. This is expected, especially if you move, sweat, change position, or if the strap grip is reduced.

When Stro is fitted correctly and you are sitting still, you should not need to adjust the strap too often.

Check the strap position during use. If the strap has moved upward from the root/base of your neck, pause and adjust it back down before continuing.

If the strap slides upward repeatedly, moves too easily, or does not stay near the root/base of your neck long enough for normal seated use, check whether the strap is wet, sweaty, dirty, oily, worn, incorrectly fitted, reversed, or no longer gripping properly.

If your anatomy, clothing, strap fit, or device position makes it difficult to keep the strap at the root/base of your neck, contact Stro support for help with fit. If the strap cannot stay in the correct area at all, Stro may not be able to work properly for your body.

Step 12: Keep your gaze and posture appropriate

Use Stro while sitting upright and looking generally forward.

A slight downward gaze toward a laptop, keyboard, notebook, or desk is fine if your neck and body remain comfortable and controlled.

Do not use Stro for long periods while looking down toward your hips, stomach, or lap, such as texting with your phone low against your body.

If you need to look down for an extended time, remove Stro first.

Do not lean forward abruptly with your neck or upper body while wearing Stro. Do not wear Stro while doing activities that require you to lean forward often or for longer periods.

Step 13: Start gradually

Stro should be introduced gradually, similar to how fitted orthotics, postural supports, or a new training routine are often introduced slowly rather than used for long periods straight away.

When first using Stro, start very slowly.

During the first week, consider using Stro for only three short sessions, with rest days in between. You can choose any days, but the aim is to give your body time to adapt between sessions.

If you are unsure, start with around 5 minutes.

The aim is to finish each session before you get tired. If you feel fatigued, strained, dizzy, uncomfortable, sore, achy, or unwell, or if you have a fever, do not use Stro.

Increase use gradually only if:

  • the device feels comfortable

  • the weight feels manageable

  • the strap grips properly

  • the strap stays near the root/base of your neck

  • the device stays correctly positioned

  • your jaw, tongue, teeth, neck, shoulders, back, muscles, and joints feel comfortable

  • you can sit upright without strain, bracing, pain, or discomfort

After the first week, you may gradually increase session length if short sessions feel comfortable and controlled. A simple approach is to add around 5 minutes at a time, only when your body feels ready.

Stro is a form of posture practice. Like training or sport, more is not always better. Train smart, start light, rest between sessions, and do not push through pain or strain.

If mild fatigue or light dizziness occurs after using Stro for too long, stop use, rest, and reduce your session length next time.

Do not increase your use time until short sessions feel comfortable and controlled.

When to stop and adjust

Pause and adjust Stro if:

  • the strap has moved upward

  • the strap is no longer at the root/base of your neck

  • the device has moved too low or too high

  • the device is near or above your collarbones

  • the device top edge is not sitting roughly 0–4 cm below your collarbones

  • the strap has twisted, folded, or bunched

  • the device feels unstable

  • the device or strap is not sitting flat against the skin

  • the device is swinging or moving more than expected

  • your posture starts to feel strained or forced

  • your jaw, tongue, teeth, neck, shoulders, back, muscles, or joints feel strained or uncomfortable

Stop using Stro and contact support if you cannot achieve a stable and comfortable fit.

When not to use Stro

Do not use Stro while:

  • standing or walking around

  • bending forward

  • leaning over another person

  • breastfeeding, bottle feeding, holding, changing, bathing, dressing, or caring for a baby or child

  • lifting or carrying heavy items

  • cooking or cleaning

  • exercising, running, jumping, climbing, cycling, or driving

  • operating tools or machinery

  • wearing a backpack, shoulder bag, crossbody bag, baby carrier, sling, harness, or other straps

  • wearing other weighted items

  • travelling in a moving car, bus, train, bike, scooter, boat, or airplane

  • sleeping or lying down

Cleaning and hygiene

Use Stro on clean, dry skin.

Wash the sleeve regularly, especially after sweating or when dirty. Follow the care instructions provided with the sleeve.

Do not share an unwashed sleeve with another person.

Dry the strap and your skin if sweat or moisture reduces grip during use.

Strap replacement

The strap is a consumable part and will wear out over time.

Replace the strap if:

  • the silicone/grip layer is worn down

  • the silicone/grip layer is peeling or separating from the fabric

  • the strap has reduced grip

  • the strap slides too easily

  • the strap is stretched, torn, frayed, weakened, or damaged

  • the strap no longer keeps the device stable and controlled

Do not wait for the strap to fail before replacing it.

Getting help

Before contacting support for general usage questions, check the Stro FAQs, Fit Guide, and community forum. Many common questions about fit, strap positioning, strap grip, session length, seated positions, clothing, and getting started may already be answered there.

For new issues, product faults, safety concerns, damaged parts, strap failure, reduced strap grip, clip issues, unusual symptoms, or anything not answered in the FAQs or community forum, contact Stro support directly.

Do not rely on the community forum for urgent safety, medical, or product-fault issues.