The biggest in BT50 scale, this large one piece fin unit is an exact scale replica of this highly popular scale subject. There are other larger scale offerings on the market but not we have a smaller robust offering. Due to the material limitations at this smaller scale, the smallest of details will be only a little soft, but you will none the less have ALL the detail depicted of the real thing. This is, like others in my 'hawk' series, for standard 18mm engines. I recommend additional motor mount tube length and additional support ring(s) for a strong mount connection. Beyond this, it is the end users responsibility for the design, construction, safety and stability of any scratch-built rocket design. Please use at your discretion. Also, If already purchased please contact me. I would like some real photo images to show off the finished product.