These motor retainers from Aero Pack are super simple and have a really clean look. They're designed to be bonded to the back of a rocket's motor tube and the twist on & off retainer cap allows for easy loading/removal of rocket motors before/after your flight. They're made of aluminium and are coated with a smooth black anodised finish.
 
FREQUENTLY ASKED QUESTIONS
 
What does a retainer do?
A retainer holds the motor inside the motor tube and prevents it from sliding out the back of the rocket. Retaining the motor during flight is crucial because when the ejection charge fires at apogee, the motor wants to shoot out the back of the rocket (Newton's 3rd law: equal and opposite reactions).
 
Which motors does this retainer work with? 
All of them! This type of retainer works with all brands of motors (both Cesaroni and Aerotech) and all types of motors (both single use and reloadable)
 
What epoxy should I use?
The motor retainer is in direct contact with the back of the motor case and can get extremely hot during flight. This means you need an epoxy that can survive high-temperatures, such as JB Weld Original, or if you're not the patient type (like me), you can use the quick-set alternative JB Weld KwikWeld. You should be able to find this at your local Repco or Jaycar electronics store (not usually sold at Bunnings).