Weaver made a 1x(K-1),1.5x(K-1.5), 2.5x(K-2.5) and 3x(K-3) in straight tube scopes and the variable 1.5-4.5 (V-4.5) and later a 1-3x(V-3). The K-1's were to meet certain state zero magnification rules for MZL seasons. I still run a couple of K-1.5's on rifles set up for close in deer hunting one a German drilling and the other a Sav 99 in 375 Win..
They work ust fine out beyond 100 yards, target shown is at 100 yards.