NPC stocks many specially sized mounting rings for use in various optical mounts. Rings with 1″OD, 2″OD, 3″OD and 4″OD are available. Smaller sizes such as 0.75″OD and 0.50″OD are in stock as well as other odd sizes to enable short lead time.
To provide more options and flexibility in design NPC now provides our standard 3″ID, 4″ID and 5″ID rings with an 8-32 threaded side hole for post mounting.