Usage Tips:NOTE: Quantity is per tube.You must select quantity of 2 for DUAL TUBE Systems The package only includes the Focusing aperture, not the night vision device. Please check the quantity when placing the order. FEATURE: The Focusing aperture is the most advanced Night Vision Goggle (NVG) accessory on the market, allowing the operator to see objects from 3 It incorporates a smooth action, high performance optical iris that can quickly be adjusted open or closed depending on the amount of ambient light. Additionally, the Focusing aperture offers a high-quality Corning Glass sacrificial lens that can quickly be replaced without tools. Provides the ability to see objects at all distances without adjusting the focus on Night Vision Goggles. Infinitely variable from open to close to allow the optimal amount of light into the NVGs and maintain auto-focus capability. Clear front sacrificial lens to protect lens of NVGs and prevent dust and debris from entering apparatus. Rapid adaptation to ambient light by turning the adjustment ring, opening or closing the iris. Easy and secure attachment to the end of NVGs. Compatity models: TYPE 1 VARIANT (NAVAIR) 37mm OD AN/PVS6 AN/PVS-7 AN/PVS-7B/D ANVIS-9 AN/PVS-14 NEPVS-14 AN/PVS-23 (F5050YG) DTNVG DTNVS RNVG TNVC-BNVG-M (Artemis) MOD3 TYPE 2 VARIANT (GROUND) 34mm OD AN/PVS-15 AN/PVS-18 AN/PVS-31A BNVD MUM-14 GPNVG