Size:80x224mm Power Interface:Optional H20-4 pins waterproof air plug. The air plug marked "1 ","2"," 3"," 4", "1 ","2 ","3" were connected to inverter (U, V, W), 4 connected inverter ground. Power:2.2kw Voltage:220v Current:10A Frequency:0-400Hz Speed: 0-24000rpm Runout Off:Less than 0.01mm Diameter(mm): 80 Bearing Type: 2 x 7005 P4 DT & 2 x 7002 P4 DT 4pcs fully sealed angular contact bearings Collet: ER20 Main Application:Engrave for wood,bamboo,normal PCB,PVC,PMMA,plastic,duotone board(ABS)and etc nonmetal, also can engrave on gold,silver,copper, aluminium,Pb etc soft metal surface working.(Please pay more attention, this is wood working spindle, only can used for wood working and aluminum working,please don't use it for steel. If you need steel working,please check the metal spindle,thank you!)