ST 100 Mountain Bike Helmet - Black



Made for Designed for protecting your head during your first mountain bike rides.
Easy to adjust and comfortable, the Rockrider ST 100 mountain bike helmet protects your head from impacts. Enjoy its 9 ventilation holes that are larger for better ventilation.


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User comfortPut on a well-fitting helmet with foam pads that you can forget you're wearing.
StabilityAdjust the helmet to your head using the adjustment wheel.
VentilationBreathe: its 9 large ventilation holes let air move through.
Ease of useEnjoy: Y-shaped straps stitched under the ears for a snug fit.
Waranty2 Years
Technical Information

To figure out your helmet size, you need to measure your head. 1/ Get a tape measure 2/ Place it around your head, about 1 cm above your eyebrows and ears. Do not pull too tight. You will be able to tighten your helmet. 3/ If you are between sizes, choose the larger size. This mountain bike helmet is available in two sizes: M: 53 - 57 cm L: 57 - 62 cm Please note: for safety reasons, helmets cannot be returned.
We recommend replacing your helmet in 2 cases: 1/ After a fall In the event of a fall, the material of your helmet can deteriorate or even break. Sometimes, you won't even notice. That is why we recommend replacing it if you have the slightest doubt. 2/ After 5 years of use The foam of your helmet degrades over time. It can deteriorate due to impact, where it is stored, the climate, and its use. We recommend replacing your helmet at least every 5 years
Follow these 2 quick steps to adjust your helmet in 5 minutes: 1/ Clip the 2 straps with the buckle: check that you can still slide 2 fingers between the strap and your chin. 2/ Finally, adjust the tightness around your head. The helmet should be in contact with your head, without tipping forward, backward, or sideways, even when you're moving.
This helmet is not adapted to attach a headlamp or other lighting source. Do you want to film your rides with a mountable camera? For your safety, we recommend attaching your sports camera directly onto the handlebars or on your torso with a suitable harness.
The helmet can seem restrictive at first. The Rockrider team is unanimous: for mountain biking, helmets have an important role to play. Moreover, we all wear a helmet. For us, helmets are essential. Don't forget to wear one! ,)
Weight270 g in size M
Information / Concept / Technology
Foam : 100.0% Expanded Polystyrene (EPS) Shell : 100.0% Polycarbonate (PC) Buckles : 100.0% Polyoxymethylene (POM) Webbing : 100.0% Polypropylene (PP)

Product test
Our engineers have all of our products tested by mountain bikers in real conditions. These tests complement the tests we do in the lab and mean that we can approve our products before they go on sale. This helmet is a safety device. For this reason, we perform numerous tests on it, in particular, those required by safety regulations. This helmet complies with standard EN 1078 for cycling, skating and skateboarding helmets.

Stockage tips
Store the helmet in a dry place away from direct sunlight, and avoid high temperatures (> 60°C). Clean the outside with a simple soft sponge and neutral soap.


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Good helmet
Used for 2 to 8 weeks
Son liked the shape and the fact it will deflect rain thanks to the front lip
Used for 2 to 8 weeks
Made me felt like a big kid. Sturdy and just how I like it. Now I no longer miss my childhood memories as I feel like a big kid cycling.

A value for money
bike helmet
Used for 2 to 8 weeks
fits well and good value for money comfortable
Not bad
Used for 2 to 8 weeks
Not a bad helmet. Like the tightening feature on the bag so it’s custom fit
Good product.
Used for 1 week or less
Look is good. Fits well. The size adjuster provides the good fitting. Very light and hard. Comfortable to wear and ride. Go for it.
Stylish accessory
Used for 1 week or less
It’s a great looking helmet and adds to your overall appearance as you ride your favourite bike(s). Good grip on the head with the straps and buckles. White looks trendy. However, the visor like part of the helmet obstructs while riding in view and also physically. May be tougher for intermediates/beginners like me but ok for pros.
Btwin Helmet
Used for 3 to 6 months
Riding bicycle is good thing, but without wearing helmet it is not safe for any rider.

Btwin provides me light weight, super aerodynamic and adjustable helmet, which makes my ride safe and secure.
I never go for ride without protection.
Great helmet at great Price
Used for 2 to 8 weeks
It's perfect for daily casual rides though it needs more reflectors at back and light fixing holders which are much needed to alert speeding traffic from behind.
Nice Product
Used for 2 to 8 weeks
it was a nice product
Bit expensive for its material.
Used for 2 to 8 weeks
Bought it for around 1400. Can be brought down to 800 or 900 taking into consideration the material used in its manufacture.
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