LP-1  Donegan OptiLOUPE®  2.5x swivel loupe, this is an add on glass lens loupe for Donegan Optivisors and similar headband magnifiers. These will fit all Donegan models as well as all our all HVM models. This is easy to install add on lens will give you 2.5x magnification on the one eye.  the LP-1 can be installed on either eye.