Applied in fire rolling door control automatically. When fire, it will close fire door according to the signal of heat and smoke detector. Liable to close hierarchically or timing. Beautiful appearance. Durable. Model EA-40 \ DH-ERSF3 \ DH-ERSF4 Voltage DC 24V Current DC0.3A Surrounding temperature range -10～+40°C Increment operator 3.5～4.5kg