WallMaster is equipped with a braking system for slow, safe belt retraction and is supplied with a wall receiver and the wall plugs and screws required for mounting the unit. The WallMaster Twin is a wall mounted retracting belt barrier featuring a unique Twin Belt configuration..WallMaster Twin 350, Black, 10' Dark Green Belt The unitâs steel housing provides the durability needed for working environments and the compact design will not create an obstruction in restricted spaces such as corridors and doorways.