Standards And Brackets

24 in. (610 mm), 36 in. (914 mm), 48 in. (1220 mm), 60 in. (1520 mm), 72 in. (1830 mm) (5)
4 in. (102 mm), 6 in. (152 mm), 8 in. (203 mm), 10 in. (254 mm), 12 in. (305 mm), 14 in. (356 mm), 16 in. (406 mm), 18 in. (457 mm), 20 in. (508 mm) (2)
6 in. (152 mm), 8 in. (203 mm), 10 in. (254 mm), 12 in. (305 mm), 16 in. (406 mm) (3)