This is the most universal base in the industry. The swivel adaptor allows the air terminal to level under most conditions. It can be secured with screws, nails, 1/4” bolts, 1/4” drive-in anchors, or an adhesive. Bolt tension cap can be turned so the cable can run horizontal or vertical. Perfect for skylights, domed or gently sloping roofs, or any uneven surface. Furnished for all air terminal sizes 3/8”, 1/2”, and 5/8”. Specify when ordering. UL Listed