Von Duprin 9847/9947 Concealed mounted vertical rod device for all types of single or double doors, UL listed for panic exit hardware. Devices are ANSI A156.3 2001 Grade 1. The 9847 device has a smooth mechanism case and the 9947 device has a grooved case. The concealed vertical rod device is non-handed. A fluid damper decelerates the pushpad on its return stroke and eliminates most noise associated with exit device operations on all devices. The EL feature allows for the remote unlatching of exit devices. A control station operator can flip a switch to retract the latch bolt and immediately change an exit door to push-pull operation. A powerful, continuous duty solenoid retracts the latch bolt, either for momentary unlatching, or for extended periods of time. The electronic latch feature is an alternative to manual dogging. EL/QEL devices are also useful with automatic door operators, and may be applied to fire-rated applications when under the control of an automatic fire alarm system. UL approved for Class II circuit applications. The EL/QEL option does not include the power transfer from door to frame, the power supply, or the control operator. Refer to EPT-2 power transfer and the PS914 power supply.