Progressive Dynamics PD5110610V 5100 Series Automatic Transfer Switch - 120 VAC, 30 Amp w/Screw Connection Quick change circuit board is easily replaced in the event of failure, no need to disconnect and reinstall the entire unit Time delay feature ensures generator voltage is at a stable level before transfer occurs Built-in strain reliefs allow the installer to simply push the branch circuit wires inside the unit for connection, eliminating the need to purchase and install separate strain reliefs for each circuit Screw-type wiring connection One-year limited warranty