21700 Three-Cell Strap-Down Cradle
A strap-down cradle for three 21700 cells lying side by side. It's for power banks, e-bike packs and high-drain flashlight builds, where almost every printed holder is sized for 18650s. It has two 22.4 mm saddles on a 25 mm pitch, so 21.0–21.7 mm cells drop in with 2.6 mm walls between them. The open ends take cells of any length, including 76 mm protected cells. Slots for a 20 mm hook-and-loop strap and four 4.5 mm M4 holes are on a 108 x 60 mm base.
electronics 21700 battery-holder cradle
⚠ Flagged: battery or DC power. Not for safety-critical use without independent engineering review.