Znen Lance 4 pin Small Rectifier regulator
This Current Rectifier, size is 1 1/4" x 1" x 1" and has a 4 prong male connection.
See 2nd picture for wiring layout, 3 prongs are to yellow wires and 1 to a white wire. Has XDZ and a date code stamped on the epoxy filled portion.
Znen lists this part number as 150T-E/022 rectifier
This regulator is known to be found in ZNEN produced Classic scooters like Lance Vintage, fly scooters and Motofino Il Bello models, BMS Heritage, and probably many other that have 11 or 12 coil stators.
