Steampunk IRIS APERTURE Monocle Goggle Victorian Brown Leather.

This Iris Aperture Monocle is unlike any other on the market, hand crafted and designs by us. This monocle is made with solid brass, aluminum, and stainless steel. The iris aperture lever allows you to smoothly slide up and down to adjust the amount of light coming in, much like the "F-Stop" of a camera lens. The apertures adjust seamlessly from fully open 1.15 inch ( 29.25 mm) to the smallest aperture diameter of .30 inch (8 mm) .  This monocle features interchangeable lenses. Simply remove the five front screws and pop in a different color lens. The eye piece eye measures 2 inch (50 mm) per diameter and includes 3 lenses in gray, red and blue lens. The leather eye cup is professionally-stitched.

Video of the iris goggles aperture in action can be view from YouTube.com at the link below.
//youtu.be/0QbMsUxfAPM