Master Lock Solid Body Padlock 19mm. The Master Lock No. 120D Solid Brass Padlock features a 3/4in (19mm) wide solid brass lock body that is strong, durable and resists corrosion. The 5/32in (4mm) diameter shackle is 7/16in (11mm) long and made of steel, offering resistance to cutting and sawing. The Limited Lifetime Warranty provides peace of mind from a brand you can trust.