The Headplay Personal Cinema System(PCS) was originally intended to be used indoors only, so there was no solution to block sunlight from coming in and ruining your view..So we came up with a solution .. The new Headplay Ski Mask Add-on blocks sunlight and is made from comfortable, breathable materials. This makes the Ski Mask add-on ideal for flying FPV outdoors. While wearing it, you will feel totally immersed in your FPV flight.ConstructionThe Headplay Ski Mask features ventilation on top and bottom, to keep it cool and prevent fogging. It also features adjustable high-quality straps and a triple-layer foam padding with a top cotton layer. Overall, the goggles are very comfortable and resemble high-end ski-goggle frames, which are intended to be worn for hours.Assembly-Remove (2) 1.5mm hex screws from the Headplay PCS visor.-Insert Headplay goggles into mask-Insert mask into frameYou may permanently glue the mask into the frame with silicone adhesive. It is recommended.