The 3kg Hafthohlladung (“adhesive hollow charge”) was a shaped-charge anti-tank mine developed by the Wehrmacht from 1942 onward. Three magnets around the outer rim could be used to attach it to armor plate, before the 5 second fuse detonated. The hollow cone focused the explosive lining into a superheated plasma jet, which would explosively burn through 140mm of armor. It was intended for use against pillboxes and fortress cupolas as well as tanks, and was colloquially known as the “Panzerknacker” (“tank cracker”). It was replaced in the last year of the war by the panzerfaust, which was much safer for the user, if not for the recipient. [ Source: Tank Museum, Bovington]
One in use, from “Männer gegen Panzer” (“Men Against Tanks”) — a 1943 German Lehr film used for training by the Wehrmacht in WWII:
