An automatic fire extinguisher system , comprising: a valve housing having an inlet port in fluid communication with an outlet port , the valve housing having a safety block disposed opposite the outlet port ; an extinguisher bottle configured to receive an extinguishing agent, the extinguisher bottle in fluid communication with the inlet port ; a valve assembly movable between a closed position in which the valve assembly inhibits fluid communication between the inlet port and the outlet port and an open position in which the valve assembly permits fluid communication between the inlet port and the outlet port ; a safety assembly disposed within the valve housing , the safety assembly movable between a safe position in which the safety assembly inhibits movement of the valve assembly from the closed position towards the open position and an armed position in which the safety assembly permits movement of the valve assembly from the closed position towards the open position, the safety assembly includes: an engagement member slidably disposed within the outlet port ; a blocking member having a first blocking member portion and a second blocking member portion that is at least partially disposed within a cavity defined by the safety block ; and an extension member that extends between the engagement member and the blocking member ; characterised in that the second blocking member portion includes a protrusion that is spaced apart from the end of the second blocking member portion ; and in that the system further comprises an indicator that extends through the valve housing . a valve housing having an inlet port in fluid communication with an outlet port , the valve housing having a safety block disposed opposite the outlet port ; an extinguisher bottle configured to receive an extinguishing agent, the extinguisher bottle in fluid communication with the inlet port ; a valve assembly movable between a closed position in which the valve assembly inhibits fluid communication between the inlet port and the outlet port and an open position in which the valve assembly permits fluid communication between the inlet port and the outlet port ; a safety assembly disposed within the valve housing , the safety assembly movable between a safe position in which the safety assembly inhibits movement of the valve assembly from the closed position towards the open position and an armed position in which the safety assembly permits movement of the valve assembly from the closed position towards the open position, the safety assembly includes: an engagement member slidably disposed within the outlet port ; a blocking member having a first blocking member portion and a second blocking member portion that is at least partially disposed within a cavity defined by the safety block ; and an extension member that extends between the engagement member and the blocking member ; characterised in that the second blocking member portion includes a protrusion that is spaced apart from the end of the second blocking member portion ; and in that the system further comprises an indicator that extends through the valve housing . an engagement member slidably disposed within the outlet port ; a blocking member having a first blocking member portion and a second blocking member portion that is at least partially disposed within a cavity defined by the safety block ; and an extension member that extends between the engagement member and the blocking member ; characterised in that the second blocking member portion includes a protrusion that is spaced apart from the end of the second blocking member portion ; and in that the system further comprises an indicator that extends through the valve housing . <EOS>