Arisaka’s Finger Rest is a bit different than most hand stops. It is smaller and more rounded, like the world’s tiniest vertical grip, so that it can slip between the shooter’s index and middle fingers, a technique that I use on occasion with a standard hand stop when my shooting position dictates it. This design allows the shooter to place the Finger Stop further forward on the rail which can provide additional space should you need to move your hand back on the rail as you would in a kneeling position.
At just .4 oz in weight, it is less than half the weight of most hand stops. I have written about how the weight of a hand stop is well worth the functionality that it brings. The Finger Stop would have all the same benefits at less than half the weight. Lightweight AR builders take note.
The Finger stop is available for the Centurion Arms CMR, KeyMod, and M-LOK. I believe it takes real work and ingenuity to reduce something to its simplest form. I am not sure I have ever seen a more minimalist and simple weapon control device than the Arisaka Finger Stop.