Pen grip allows fingertip control for intricate work. Ideal in confined spaces. Compatible with most rotary tools including Silverline, GMC and Dremel. Ideal for use with Silverline Telescopic Hanging Stand and Silverline Rotary Tool. Max 28,000rpm. Pen grip allows fingertip control for intricate work. Ideal in confined spaces. Compatible with most rotary tools including Silverline, GMC and Dremel. Ideal for use with Silverline Telescopic Hanging Stand and Silverline Rotary Tool. Max 28,000rpm.