Haha it is a camelback (solomon activeskin)

Also have the 2l bladder for in the backpack, but I prefer the softflasks up front. Mostly because the bladder will get warm after 25km and your back will be very sweaty. Also these flasks are more comfortable drinking and gives you the opportunity to do 2 different types of drinks (for example left just water, right side sports drinks).

The bladder really comes in use if you do ultra runs where you need >3 liters of drinks with you!