Kahuna 14ft Trampoline Replacement Spring Mat - RainbowKahuna 14ft Trampoline Replacement Spring Mat Rainbow Replacement Rainbow Trampoline Mat These mats are manufactured using the highest strength polypropylene mat fabric. This gives a very high strength while still allowing the mat to 'breathe'. The design greatly reduces air resistance, especially on the rebound. Cheaper mats using lower grade material can only achieve the required strength by using a denser weave; the downside to this design is that