NEMA 10-30P to 14-50R Splitter, NEMA 10-30 Male Plug to 10-30 and 14-50 Female Receptacle
Dryer 3-Prong 30 AMP Y Adapter Cord to RV or EV 4-prong and Dryer 3-prong.

14-50R can use for EV charging and RV travel trailer.
It can not work if the grounding wire did not connect. Please make sure your grounding wire already connected.
Use on when you have both dryer 10-30 plug and 14-50 EV charger plug, need to plugin a 10-30 dryer 3-prong 30A 240V outlet.