Regal Electronics # ST3-33. Part# 2A71-3. Class B, pc mount transformer. According to our tests 120 Vac input provides 3 Vac, 100 mA output. 1.40" x 1.18" x 1.20" high.
MCI #4-05-2016 Primary: 115/ 230Vacs Secondary: Series 16VCT @ 0.35A Parallel 8V @ 0.70A Low-profile pc mount transformer. 48 x 39 x 21mm high. PC pins. UL, CSA.