... Size:1/4...M16 4.Easy installation Channel Spring Nut/galvanized steel spring nut1) Description:channel spring nuts , spring channel nuts , ... and material:a) normal strength: made from low carbon steel, C1015, Q235 etcb) high strength: made from high carbon ... C1035, C1045, etc, And with hardened treatment.material: carbon steel, stainless steel, SS304, SS316. etc.3) Surface treatment:plain/self colour ...