... clamp 1.Universal malleable iron beam clmap 2.Size range:1/4-20,3/8-163surface finish:black,electro-z ... Light Duty Beam Clamp,Spring Steel Clamp 1.universal malleable iron beam clmap ... 2.size range:1/4-20,3/8-163surface finish:black,electro-z ... to protect against slippage Light Duty Beam Clamp,Spring Steel ...