They are about twice as thick, and a bit wider. The main thing is mounting; personal transponders can be put anywhere, whereas house transponders need to be mounted in an easy-to-access location and held in by a body clip.
SH Z-Car, Custom Crawler, 8s Savage, 12s XTM XLB 1/7 buggy, 4wd 4-link rear/IFS Pro4 truck, Custom Hyper 10 Short Course, Belt-Drive Mammoth ST 1/8 truggy, 4s 17.5 MM Pro HPI Blitz