VERSATILE: This 3.6V USB rechargeable pen style mini engraver is ideal for model makers, crafters and engravers. EASY TO USE: With a quick keyless accessory change between 2.3mm-2.4mm, it has a maximum 13, 000 RPM no-load speed. SET INCLUDES: 1 mini engraver, 2 micro USB cables, 2 brass collets (2.4mm & 3.2mm) , 2 diamond coated bits, 1 tungsten rotary burr, 2 aluminium oxide grinding wheels, 1 sanding drum holder, 2 sanding drums, 1 nylon brush.