The Mini Collimator’s small size results in affordability without compromising accuracy. Designed for precision center line alignment within tight spaces and where power sources are limited. Barrel’s outside diameter is 1.125″. Contains a single cross reticule target which is concentric to the outside diameter to less than 10 arc seconds. Target is illuminated from the rear by a low voltage battery operated Warren-Knight LED Illuminator (WK-31-1112). Length is 3.530″.