High speed steel. For intricate cutting and trimming on aluminium, brass, copper, wood and plastic. Max 20,000rpm / 3.17mm mandrel. Includes 5 x HSS saw discs: 22, 25, 32, 35 and 44mm. Compatible with most rotary tools including Silverline, GMC and Dremel. High speed steel. For intricate cutting and trimming on aluminium, brass, copper, wood and plastic. Max 20,000rpm / 3.17mm mandrel. Includes 5 x HSS saw discs: 22, 25, 32, 35 and 44mm. Compatible with most rotary tools including Silverline, GMC and Dremel.