The Castelli Free Tri Top is at first glance a very minimal piece but first glances can be deceptive. A combination of fabrics are used to achieve the best balance of hydrophobic speed in the water, aerodynamics on the bike and cool on the run.The full-length YKK Camlock zipper stays locked where you place it. We have 2 rear pockets for carrying nutrition or warmers these are carefully aero and hydro positioned so your not effectively dragging a parachute with you. and we have our little SnapLock fasteners so you can clip the top to your shorts on the bike and swim for the best possible dynamics - then release them for the run.The Castelli Free Tri Top with a little more going on than first looks suggest.Key Features:Thoroughly engineered triathlon race top.Speed Freak ventilated race fabric on the front.Velocity mesh back gives wind-tunnel proven speed on the bike.Snap Lock fastener at the lower back allows top and shorts to lock to prevent ride up on the swim or bike leg.YKK Camlock zipper.Free Aero2 hydro and aero optimised pockets.Soft finish armholes reduce the risk of chafing.Weight 58g (L) .