Four-way ratchet design. For mounting to deck or bulkhead. Has 9/32" access hole for cable. Standard 1" - 14 male thread.

19521: Base: 2-5/8" x 3-5/8". Center to center: 1-7/8" x 3" 
19531: Base: 2-1/4" x 3-3/4". Center to center: 1-1/2" x 3"