304 untainted Steel Marine Cushion Clamps These cushioned clamps are of untainted steel for dominant protection from malign elements. adult riggers these untainted steel clamps are the apotheosis clamps for leatherneck applications.Specification : Clamp work diameter : 6.3 mm -LRB- 1/4 inch -RRB-. Clamp screw hole : 6.5 mm. Clamp width the rubber cushioned : 15 mm.Package : 20 Pack .