Shure 90M2150, 51A38, 51C38 Microphone Audio Transformer, Lo-Z to Hi-Z Harp Mics
100% Equivalent to Shure #51A38, 51C38. -- tiny - small size - LOW PROFILE so it canfit in most Bullet Mic Shells. DC Resistance Pri:20 Ohms, Sec:2000 Ohms. Input Impedance range: 25 to 600 Ohms.