• Pre-formed shape to enhance fitting difficulty and accuracy.
• Variable material thickness to put protection where it is needed, and comfort where it is desired.
• 1.0mm on the inside, 2.0mm on the outside
• For athletes over 5′ tall
• Works with braces (with braces must be fitted by a dentist)
• Non-toxic: BPA, BPS, Latex, PVC, Phthalate free

1. Wash your hands and the material with soap and water.
2. Heat water in a small bowl to approximately 170° F / 76° C (hot to the touch, but not boiling).
3. Place your SISU 3D Mouthguard into the hot water and wait until it becomes soft and pliable (use a fork or other utensil to determine mouthguard softness). It’s essential that you do not let the softened guard fold on itself. The material will glue together, making it difficult to reshape.
4. Holding the mouthguard with both hands, carefully insert the mouthguard. Make sure the back inner ridge does not fold in on itself. Bite down gently – do not make deep teeth marks.
5. Once your SISU is in the proper position, close your lips over the guard and put your tongue to the roof of your mouth. Gently create suction by swallowing until the material has hardened to a snug, perfect fit. Keep the mouthguard in your mouth for 3-5 minutes to allow the shape to set. After the guard is set, it should be snug enough that it won’t come off your teeth without using your fingers to “help” remove it.
6. If you have made a mistake don’t worry. Every SISU guard is remouldable up to 20 times. Simply place your formed SISU back in the hot water, let it soften and then start at step 3 again.

Christmas Returns

Products can be returned up to Friday 16th January 2026. Terms and exclusions apply, please see below.

Delivery

Free delivery when you spend over £150 with a maximum weight of 30kg.

UK Standard delivery within the UK is £3.95

UK Express delivery within the UK is £6.95

All orders recieved before 12pm will be dispatched same day.

Returns

All orders can be returned within 14 days of purchase.

Please contact us first to recieve a returns authorisation. All items returned must be in perfect condition, unused, unwashed with their original packaging and still have their original tags attached. For more information please see our returns page here

For hygiene reasons mouthguards, groin guards, hand wraps and ankle supports cannot be returned unless the packaging is sealed and unopened.