Lortone 3A Single Barrel Tumbler. Model 3A tumbler with a simple 1.3kg (3 lb) capacity barrel offers the user economy and performance. Designed for years of trouble free service, the 3A is a real workhorse. The barrel is hard rubber to minimize noise and the durable motor will last for years. Use with steel shot to burnish your PMC pieces, can also be used for polishing silver components. The unit is approx 245mm long, 155mm wide and 145mm high with the barrel in place.