Aeropack 75 mm Retainer Base, L [RB75L]. Madcow Rocketry / Aeropack : Rocketarium Model Rocket Kits, parts and launch supplies

75 mm Retainer Base for LOC/Precision Heavy Wall motor tubes. (3.18" OD)

Light-Weight Body Only, For 75mm Motor Mount Tubes "P"
Precision Machined 6061-T6 Aluminum With Mil-Spec Type II Black Anodizing
Large Quick-Turn Threads For Fast, Tool-Free Motor Change
Installation: Simply Bond To Motor Mount Tube With JB Weld™ And You're Done!
Just Slide Motor In And Thread On Cap, That's It!
Can Be Installed On Existing Rockets With Motor Mount Tubes Extending 3/4" Or More Below Lower Centering Ring