Sturdy & RELIABLE MATERIAL The 5kg swivel cup made of sturdy polycarbonate has the leakproof function and long service life STRONG POWER - Adopt the principle of centrifugal movement, high-efficiency polishing, improve work efficiency by 5 to 10 times. FLEXIBLE ADJUSTMENT - The jewelry polisher tumbler with bidirectional rotation and 5 speeds & timers from 10 to 60 minutes The working time and speed can be adjusted according to different materials and different surface requirements USERFRIENDLY DESIGN - The tightly designed buckle has good air tightness, worry-free. The bottom of the jewelry cup machine is provided with a wear-resistant rubber pad: non-slip, stable and shockproof. VARIOUS APPLICATION - for jewelry, steel, iron, copper such as surface polishing, chamfering, trimming, coarse and fine grinding, precision polishing, black spot removal and fine grinding.