Which grenade is primarily used for signaling?

The primary purpose of the M-18 Smoke Grenade is signaling, which allows troops to convey information visually to other units or to signal an emergency. The smoke produced by the M-18 can be seen from a distance and can communicate a variety of messages, such as marking a landing zone or indicating a specific location for friendly forces.

Using colored smoke, such as red, green, or yellow, enhances visibility for friendly forces while obscuring the enemy. This characteristic makes the M-18 advantageous for tactical communication in various combat situations.

In contrast, the other grenades serve different purposes. The M-67 grenade is primarily an offensive fragmentation grenade designed for use against personnel and lightly armored vehicles. The Illumination Grenade is intended to light up an area, offering visibility at night or in low-light conditions, while the White Phosphorus Grenade is typically used for creating smoke screens or incendiary effects, rather than for signaling.