US Cartridge, 40mm Cluster Star, M585, XM585, XM663, XM664
These are Army grenade launcher fired projectiles containing five nose ejected, free falling pyrotechnic star pellets, and are used for signaling. Total intensity ranges from 14,000 to 55,000 candlepower. The color of the burning pyrotechnic is as follows: XM585 and M585 (XM585E1), white; XM663, green; XM664, red.
The projectile body is painted white, with identifying information stenciled on the side. The ogive is painted the color of the burning pyrotechnic, and is embossed with the raised letters W, G, or R, corresponding to the colors white, green, or red, respectively, the ogive of the cluster star projectile has five raised dots around the outer edge, signifying five stars.
Nothing else to see.
Collaborative Ordnance Data Repository