It's not a secret for everyone that rotaries are more stable with RCA connection. Coil machines are better with classical clip cord comparing to RCA cord, which usually just drops off because of the frame vibrations. No need to buy expensive power supply for two machines or install RCA connector on every of your coils. For those who can't imagine their everyday work without simultaneous usage of coil and rotary machines we made this adaptor with RCA connector. It's so easy now to switch between coil and rotary, all you need is to cut plastic cord sleeve in place where your RCA cord is connected to adaptor. Use your RCA cord when you need to work with rotary, connect adaptor when you switch to coils. As usually all connectors and accessories only by quality brands and 1 year of warranty by VladBlad Irons