Estes 1602PK2 B4-4 Model Rocket Engines, 6 Count – 18mm Single-Stage Motors with Starters & Plugs 17mm (11/16”)

17mm (11/16”)

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Flint glass petri dish bottom for culturing cells and other scientific applications

Cork Backing - The back of the ruler is lined with cork for easy and comfortable use

Estes 1602PK2 B4-4 Model Rocket Engines, 6 Count – 18mm Single-Stage Motors with Starters & Plugs 17mm (11/16”)PLEASE NOTE: These are 18mm diameter engines. Please refer to the instructions that came with your rocket (or the rocket's product description) to determine engine compatibility. 2 Packs of Estes B4 4 engines total of 6 engines (each pack includes 3 engines, 4 starters, and 4 starter plugs) The B4 4 is a single stage engine designed for model rocket flights weighing less than 3. 5 ounces, including the engine Recommended for use with the Baby Bertha,