This rotary tumbler is quite simple to operate and gives an excellent finish to materials such as rocks, stones, coins, clean cartridges, brass, etc. It has a clear barrel with locking bar closure. It is excellent for studio and small jewelry projects like polishing gold and silver. The jewelry polisher tumbler features two-way rotation, 5-speed adjustment, and a 10-60 minutes timer. Different materials determine different working times and speeds. Reliable Material: The 3 kg / 5kg rotary tumbler, made of tough polycarbonate, features an integrated molding technique, leak-proof design, and long service life. The new gear transmission structure ensures a smoother and more stable operation without breaking worries. Powerful Performance: This jewelry tumbler utilizes iron beads or steel balls to work on the surface of the workpiece. Taking the principle of centrifugal motion, this jewelry tumbler can improve the polishing efficiency 5 to 10 times. This rotary tumbler can improve the workpiece's specification precision and delicate shapes, forming a smooth and gloss surface. Flexible Adjustment: The jewelry polisher tumbler has the function of bidirectional rotation, 5 speeds, and a timer from 10-60 minutes. The working time and speed can be adjusted according to different materials and surface requirements. User-friendly Design: The tightly designed buckle has good air tightness. No need to worry about leakage. The bottom of the jewelry tumbler machine adopts a wear-proof rubber pad, which is non-slip, stable, and shock-proof. Various Application: Ideal for jewelry, steel, iron, copper, zinc, aluminum, magnesium alloy materials such as surface polishing, chamfering, trimming, rough finishing, precision polishing, removing black spots and fine grinding.