https://jonrocket.com/shop/index.php?main_page=product_info&cPath=9_32&products_id=622
Transition - BT-50 to BT-55 - 1 Long - Model Rocket Part [TA5055] - $6.99 : JonRocket.com, Rocketry...
JonRocket.com Transition - BT-50 to BT-55 - 1 Long - Model Rocket Part [TA5055] - Balsa BT-50 to BT-55 transition with one-inch taper.
https://challengerlighting.com/products/table/ta5055/
TA5055 | Challenger Lighting
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