These couplers are for C6 and C7 fitment, but please note that they are application specific. The C6 ZR1 and C7 (M7/A8) version is different from the non ZR1 C6. These are made in house from 6061-T6 aluminum. Please note you may experience increased driveline vibration as is the case with any solid coupler. When used on automatics, you will need to use the billet flex plate from RPM Transmissions that eliminates the pinch collar (this piece will make a lot of noise).
These are sold in pairs, and the price is per pair.