Estes 29mm Screw-on Motor Retainer

18mm "C" Motor Mount - Estes Model Rocket Kit Parts

BT-60 X Two 18mm Centering Ring Set For Estes model rocket kits laser cut ply.

Laser-Cut Rocket Stand for 18mm (C-Engine) Rockets New - Not Estes

Estes 24mm Screw-on Motor Retainer

ESTES SENTINEL FLYING MODEL ROCKET, SCRATCH BUILT, NEVER FLOWN, uses 18MM eng.

Estes Flying Model Rocket Kit Accessory Motor Retainer Set 24mm(2pk) EST 9751

BT-55 X 18mm "C" Centering Ring Set For Estes model rocket kits laser cut ply.