Best out there - Trijicon Electro Optics SNIPE-IR 35mm Clip-On Thermal Imaging Monocular

if you want to use one thermal on more than weapon then this is the one. Developed to use with 4x acog but will work with other low magnification optics. Returns to zero everytime. This works well in stand alone mode with a 3x magnifier . Simply put you can switch between 2 weapons this way and allways be on target.Clearest image of any thermal.