The world's favourite heavy-duty clamp. The revolutionary patented design of Supra clamp makes it the strongest on the market and the unique swivelling bridge means that Supra can be mounted in the most dificult applications. Where reliability, strength, high torque and suprealative hydraulic performance are needed, industry professionals ask for Supra by name. Available in W2 and in W4 material qualities. Supra W2 Materials: Ban: AISI. 430 Stainless steel. Bolt: Steel Cr3 white zinc plated. (CHrome 6 free).