Material: Aircraft aluminum Stroke Length: 2.0mm to 4.2mm Six Options Adjustable Stroke: 2.0, 2.4, 2.8, 3.3, 3.7, 4.2mm Operating Voltage: 5 - 12V DC (Recommended not to exceed 10v) Rpm: 12V/10000rpm ± 10% Switch Frequency: 60 - 170 Hz Needle Protrusion: 0 - 4,5 mm Dimensions(Ø X L): 32 - 39 mm x 135 mm Weight: 8.7oz (247g) with power pack- Bigger Grip Battery Capacity: 1600mAh Recharging Time: 2 hrs Power pack Working time: Approx. 4.5 hours