Castelli perfetto light 2castellis perfetto light 2 was developed due to the pros asking for something not as hot as the gabba but warmer than the perfetto vest so how did they do it well castelli started from the gabba and made the back in nano light fabric which is the same fabric as their nano flex tights but without the brushed fleece inside what this does is give this short sleeve jacket a lot of breathability keeping you from overheating inside castelli lightened up the perfetto 2