The low-profile, threaded twist-lock surface mount base measure just 5/8 in. (15.9 mm) tall and 7 in. (17.8 cm) in diameter with a 5-3/4 in. (14.6 cm) bolt pattern. There is no need to cut a hole in your deck. Made of durable anodized Aluminum with a brushed Satin Finish, it is perfect for swim platforms, boat decks, pontoon boats, or at home on the patio, balcony or deck.