... ,din931size of the product: all sizesurface of the product: yellow zinc plated , zinc plated , black , plain , H.G.Dpacking of the product: bulk , box ... or other special materials. For finishing, we provide black oxide, zinc electroplating, phosphate, copper plating, mechanical galvanization, hot dip galvanization, and ... , you are welcomed to visit us. hexagon bolt DIN933 yellow zinc plated