Mighty Mule FM502 RB570 Replacement Transformers
Transformer, 18 Volt/40VA, MM Series UL ONLY
The RB570 is an 18 Volt AC transformer for use with all, UL Rated, Mighty Mule automatic gate openers. The transformer maintains battery charge by providing a trickle charge of power to the gate opener battery.
Replacement Transformer
For Mighty Mule after March 2000 UL325 changes
Compatible with RB709U Receiver (garage door applications)
Use this transformer for the Mighty Mule FM500 / FM502 and FM350. They will have a warning beeper feature built-in to the control box, whereas the older ones do not. Number of cycles per day usage does not matter.