Plywood fins and centering ring upgrade for the Estes Doorknob Model Rocket kit

Description

Plywood fins and centering ring upgrade for the Estes pro Series II Doorknob Model Rocket kit #9720 Condition is "New".
The Doorknob is a cool scale model of a real-life 1950's nuclear missile. It's a big, 3 inch rocket over 26 inches tall, but the balsa fins included in the kit make it pretty fragile. This kit allows you to dramatically stengthen the rocket and fly it on higher-impulse motors.
This is a plywood upgrade set of fins for the Estes Doorknob kit. The kit includes 4  fins and 3 centering rings that are one-to-one copies of the balsa and cardstock fins and rings in the Doorknob kit. These fins are drop-in replacements for the kit parts and will significantly improve the durability of your rocket allowing you to use higher-power motors.
These parts are precision laser-cut from 1/8" Baltic Birch plywood.
This is not a complete rocket kit.
Thanks for looking.