This crafty bit of Soviet engineering slots into any hotshoe or cold shoe camera and gives it rangefinder. You simply look through the viewfinder and turn the dial on the rear until the images in the yellow focus zone line up horizontally and read the distance off the dial. The focus spot is quite bright and contrasty for a rangefinder but worth nothing the viewfinder window is small. The Blik is marked from 1m to 15m then infinity which sound  like a reasonable spread.