Check the listing for details. (2) Two Cox .049 .051 Glow Plug Wrenches 21530 Black 1/2 A Engine Vintage Tools. Color: Black, Condition: Used. Listed at 9.99 USD. Elevate your radio control experience with this set of two Cox .049 and .051 Glow Plug Wrenches. Specifically designed for use with Cox 2-stroke engine models, these wrenches are essential tools for R/C enthusiasts who appreciate the precision and performance of their aircraft, helicopters, cars, or boats. The sleek black finish adds a touch of classic style to your modeling toolkit. Whether you're maintaining a vintage collection or optimizing your current setup, these wrenches are compatible with a wide range of models that operate on nitro and glow fuel. The 1/2 A engine size designation ensures a perfect fit for your cylinder glow plug adjustments, providing a reliable and consistent performance for your control line free flight models.