QA1 RCK52338 Rear Pro Coil Shock System1964-1972 GM A/G-Body Single Adjustable No SpringsQA1 RCK52338 Rear Pro Coil Shock System1964 1972 GM A G Body Single Adjustable No Springs QA1 now offers bolt in rear coil over shocks for 1964 1972 GM A body vehicles. These shocks are available in single or double adjustable valving options. Single adjustable shocks provide 18 positions of simultaneous rebound and compression adjustment while QA1's double adjustable shocks provide 18 positions of compression adjustment and 18 positions of rebound