Conntek 20601-010 30-Amp 125/250-volt L14-30 4-Prong Transfer Switch/Generator Extension Cord, 10-Feet
Generator Locking Extension Cord, 3 Pole, 4 Wire Grounding, NEMA L14-30P to NEMA L14-30R Max Power: 7500W, Stays flexible in cold weather, Heat Resistant up to 221F Cable: 10FT SJTW 10/3 Application: Transfer Switches, Generator,...etc.  Approval: Plug, Connector and SJTW: UL, C-UL.