The MK1 illumination hand grenade is a ground signaling and ground pyrotechnic signal, except that the grenade burns only at ground level whereas pyrotechnic signals burn in flight or while suspended from a parachute. The MK1 should not be used in deep mud or swampy ground, which would result in little or no illumination. The grenade burns with a very hot flame and may be used as an incendiary agent. Because it is incendiary, soldiers should use caution to prevent fires that would be detrimental to tactical operations.
a. Body. The body of the MK1 illumination grenade is sheet metal.
b. Filler. The filler has 3.5 ounces of illuminating pyrotechnic composition.
c. Fuze. The fuze is a special igniter, which differs from other igniting type fuzes in that it contains a quick match rather than a powder delay train. The quick match has a burning time of 7 seconds, after which it sets off an igniter charge. The igniter charge initiates the burning process of the grenade’s filler.
d. Weight. The grenade weighs 10 ounces.
e. Capabilities. The average soldier can throw the MK1 40 meters. The filler burns for 25 seconds, producing 55,000 candlepower and illuminating an area 200 meters in diameter.
f. Color and Markings. Older MK1 grenades are white with black markings; newer models are unpainted with black markings.
Avoid looking directly at the illumination grenade as it burns, since the intensity of the light may damage the retina.
Total length: 133mm. Body length: 111mm. Diameter: 46mm.