New for 2011 ProScale Mouse is a new digital pocket scale that packs a huge performance in a small package. The design is truly unique as it not only is a scale but a functional optical mouse and a storage compartment as well. The Proscale Mouse reads in Grams, Ounces, grains and carats. It is available in 100g x 0.01g and 500g 0.1g capacity. The scale offers Blue LED blacklight and requires two tripple A batteries, AAA Batteries (Batteries Included)