FISTRAL BladderFISTRAL has two different inner tubes: for the Strut with bottom section (red) and the Strut without bottom section (green). Even with the use of extra robust materials and our high demands on the durability of our products, they are of course not indestructible. In the event of a leak, it is possible to repair each individual part of the frame yourself using the repair kit supplied. However, there are also holes that are difficult to repair. For