The SP241 came with a quick-detachable mount for the M-16/AR-15 rifles and is quite possibly the fastest sighting system ever made for medium to high lighting conditions out to about 100 yards. It was produced by Singlepoint Avionics, Ltd. , Hampshire, England. Any standard one-inch mounting ring sets could be used on rifles, shotguns, or handguns. It is used with both eyes open, simply looking at the target
, and a red dot
superimposed is where the bullet strikes. It is adjusted like a standard optical riflescope with windage and elevation turrets. It is also the most rugged, virtually indestructible system.