The black (4.25" size) and silver (3.5") opening mechanism works by turning the knob and the top will open, insert new blade and then firmly close to secure the blade (butterfly style).One of other silver(3.5" size) old fashion opens and assembles into 3pcs.You can use any other brands of double edge blades.Ideal for hair salons, barbershops and household use.Comes in a beautifully crafted packing.Hard to find productWhat's included (3pcs old fashion vintage razor)?-1 x metal alloy chrome finish classic safety (butterfly style).-1x metal alloy black finish classic safety (butterfly style).-1x metal alloy chrome finish classic safety (3pcs style).-4packs (20pcs) super-max brand double edge razor blades.-Each comes in a beautifully crafted packing.