6-20 standard 20A 240 volt household outlet, found in homes and motels for running in-wall Air Conditioners, also found occasionally in residential garages. 6-50 standard 50A 240 volt 3-prong outlet, found in shops and garages used for large welders. 10-30 standard 30A 240 volt 3-prong Dryer outlet found in homes build before 1996

The most common of these are either Type 6 (2-pole, 3-wire grounding connectors that have two hot wires and a ground) or Type 14 connectors (3-pole, 4-wire connectors that have two hot wires, a neutral and a ground). For most combinations of type and amperage rating, there are straight blade and locking versions (see Figure 5).