The Crimson Trace Rail Master Laser is an instantly activated universal laser sight for Picatinny or Weaver rail equipped pistols or rifles. This Crimson Trace Rail Mount Laser Sight provides a universal fit, and it is built with industry-leading quality, ergonomics and fit. Featuring a polymer construction, the Crimson Laser Sight is durable and lightweight. This Crimson Trace Rail Master Laser requires one 1/3N lithium battery or two 357 silver oxide batteries. The battery life lasts for over four hours. This Crimson Trace Rail Master Laser measures 1.75" long x 1.2" wide x 1" high. Crimson Trace Rail Master Universal Rail Mount Laser: * Platform: universal * Material: polymer * Attachment: accessory rail attachment * Activation location: switch activation * Sighting: factory sighted at 50" * Battery type: one 1/3N lithium or two 357 silver oxide batteries * Laser battery life: over 4 hours * Laser output: 5mW red laser * Activation mode: instant activation * Laser visibility: approximately .5" diameter at 50" * Wrench size: 0.05 * Finish: polymer housing * Installation: user installed * Warranty: 3-year full warranty * Color: black * Dot size: approximately 0.50" at 50" * Model# CRMCMR201