The Philips Norelco Ultimate Premium Precision Beard Trimmer BT9810/40 is a premium beard, hair, and stubble trimmer. Including: Full steel blades and head, sleek and durable steel design; 100% waterproof; 120 minutes of Lithium Ion run time, 30 quick adjustable lengths zoom wheel in 0.2mm increments (0.4mm to 10mm range) and 1 sturdy reinforced guard attachment to get your precise, even, desired length. This trimmer also cuts hair.