Type of explosive: Eight cast blocks, 50-50 RDX-TNT shaped to form circle. Individual blocks wrapped in wax paper.

Description: The mine resembles a canvas cloth bag, disc shaped, with a snap-fastened top on the outer edge for inserting the eight blocks of explosive. Opposite the filling flap on the outer edge of the mine, is a metal adapter which is externally threaded to receive the fuze. Four equally spaced permanent magnets are attached by khaki webbing to the outer edge of the mine body. The mine is packed two to a wooden box complete with wooden shipping plugs in the fuze adapters. The fuzes are enclosed in tubular metal ca-ses sealed with a paper band and tear string. For carrying on the field, the mines are packed individually in a khaki-colored cloth pouch.

The fuze contains two springs, a compression spring a firing pin spring, the latter of which is contained in a firing pin sleeve. Four steel retaining balls fits into holes in the firing pin sleeve and notches in the firing pin, retaining the position of the firing pin. A fuze cap provides a base for the first spring and is grooved on the inside about one-third of the way up from its base. There is a safety pin which passes through the fuze body just below the base of the safety cap and between the striker and the percussion cap. The powder delay train threads into the base of the fuze body, and the detonator tube threads over the base of the delay train container.

Employment: Used as antitank or antivehicular mine, or against armored fortiforcations.

Operation: The fuze is carried separately and is secured to the mine by a locking ring. In use, the safety pin is pulled, the fuze cap given a sharp rap, and the mine either pla-ced on or tossed on armor plate within a range of ten feet. When the fuze cap is forced downward against the compression spring, its groove aligns with the retaining balls. The tension of the firing pin spring forces the retaining balls into this groove and also forces the striker down onto the percussion cap.

Remarks: Test detonations of this mine indicate a distinct "Monroe Effect" at the junc-tion of the inner edges of the explosive blocks. One mine will produce complete perforan-tions in plate up to 1 inch. The mines are frequently coupled together and when so used, will penetrate 1.5 inch steel plate.

Figure 154 – Type 99 Armor-Penetration Land Mine.