An example of strike-slip duplexes was observed in the Lambertville sill, New Jersey. Flemington and the Hopewell faults, the two main faults in the region, experienced 3 km of dip-slip and over 20 km of strike-slip motions to accommodate regional extension. It is possible to trace the lensoidal structures which are interpreted as horses that form duplexes. The lens structures observed in the 3M quarry are 180 meters long and 10 meters wide. The main duplex is 30 m in length and other smaller duplexes are also present.