A safety pin for fire extinguishers. The pin has a prong interfitted in registering holes of the extinguisher to prevent operation until removed by grasping a finger loop and extracting the pin. The finger loop is connected to a stabilizer extension of the pin fitting over the top of the trigger and biased against it to present the loop in a preselected upright position for ready access by the user. The stabilizer extension may be formed as a stabilizer loop bearing against the top of the trigger to prevent the rotation of the pin. The pin may be further provided with an upright standard extending above the trigger to receive an inspection tag or the like.