Open base, glass-filled nylon cleats with two mounting holes. 3" cleat: 5/16 max line dia., 9/16" Height, #8 FSTN 4" cleat: 3/8 max line dia., 3/4" Height, #8 FSTN 5" cleat: 3/8 max line dia., 1" Height, #10 FSTN 6" cleat: 1/2 max line dia., 1 1/4" Height, 1/4" FSTN 8" cleat: 5/8 max line dia., 1 1/2" Height, 1/4" FSTN