Does anyone miss the old Estes K-27 Honest John model rocket kit, but don’t miss the hassle of beveling fins? Well model rocketeers this one is for you! This fin unit recreates the classic M31 round but with better more accurate detailing, in a faithful reproduction using printing technology accessible to the consumer. It captures the most intricate of details, and is intended to take advantage of the use with the Estes Mini Honest John plastic nose cone available with that kit. I also have in my shop spin nozzles to modify that cone. Look for it! This fin unit design excludes the use of an engine clip much like the original Estes K-27 kit to retain the scale appearance, as well as keeping an 18mm power as the engine size. It is a friction fit design. This product is not intended to use as a modification of any specific kit or their instructions, but rather a general part to use in a scratch build with additional parts from other sources. It is the end users responsibility therefore to make sure of the rockets safety and stability for a scratch built design. I hope you like it!