Protective battery boxes are a perfect fit for the Turnigy Nanotech 1300 3S batteries that are popular for minquads and FPV racers. There's two styles, one with the SeeMeCNC blinky eyes and one without. The inside dimensions are 24mm x 35mm and they are 75mm long.

Print in any material and scale to fit other batteries. Also, flexibles would be good as they would help hold the battery in place even better

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fpv, tattu, lipo, battery, box, protector