FLY MTB is a really versatile product designed to offer mountain bikers a very light performing and resistant bottle to use without worrying about the cleanliness of the push-pull valve. Adding a detachable transparent plastic cap to protect the lid prevents the bottle to be covered of dust mud and other external agents that might land on the spout while riding the MTB on rocky off-road paths. h3Variable thickness lighter bottles.h3 The Elite FLY range is widely known as the lightest bottle ever created thanks to its 30 weight decrease compared to traditional bottles on the market. This is achieved through their variable thickness structure – they’ve got a thin middle part and a thick bottom so there’s less material used at no expense of the resistance or functional qualities of the bottle.