Castelli core mesh 3 sleeveless jerseythis core mesh 3 sleeveless jersey is designed primarily to keep you dry by moving moisture from the skin to your race jersey the core mesh sleeveless jersey is perfect for milder temperatures not hot and not cold just the middle ground most of us ride in most of the time featuresmaterial 93 polyester 7 elastane100 polyester 3d mesh fabricreduced seaming at shoulders for extra comfortwider collar to fit under aero jerseysflat waist hem to lie flat