1.Adjustable speed range.. 2.shaking plate can bear heavy load 3.Build-in timer is up to 999 hours, and alarm when time out 4.Long service time MODEL SPECIFICATIONS: US-520D, US-560D, US-580D PANEL TYPE: Digital display SHAKING TYPE: Orbital SHAKING SPEED: 30 to250 r.p.m. SHAKING STROKE: 50mm TIMER: 999 h/ m/ s POWER VOLTAGE: 110 V, 60 Hz / 220V, 50Hz PLATFORM DIMENSIONS( mm) : 400x300 600x480 965x610 OVERALL DIMENSIONS( mm) : 400x300x175 600x480x225 965x610x250 WEIGHT( Approx.) : 16, 53, 98