Fulton MX-991 18650 Battery Adapter

Description

18650 Battery Adapter for Fulton MX-991 FlashlightThis adapter allows the use of a rechargeable 18650 Li-ion cell in the classic Fulton MX-991 flashlight without permanently modifying the flashlight while preserving its rugged and reliable design.The adapter is intentionally simple and uses only a few readily available hardware components.Required HardwareBesides the 3D printed parts, you will need:1× M4x30 mm socket head screw1× M4 acorn (cap) nut2× Washers (14 mm OD / 4 mm ID)1× Compression springDiameter: approximately 10 mm (±2 mm)Minimum length: 20 mmHigh spring forceAssemblyInsert the M4 screw with one washer through the adapter body.Install the second washer.Thread the M4 acorn nut onto the screw and tighten everything securely.Insert the compression spring into the adapter.Insert the 18650 cell so the spring is compressed between the battery terminal and the screw.The rounded end of the acorn nut makes contact with the flashlight terminal, just like the original batteries did.About the springThe spring not only provides the electrical contact, but also keeps constant pressure on the battery.This absorbs shocks and vibrations, preventing flickering or momentary power loss during rough use while preserving the rugged character of the Fulton MX-991.Donations in Bitcoin Cash are welcome:qzsgcdfsqyvu09hru5l2e0k2e2rqs69x4qagyt4up9Just in case someone finds it useful and wants to contribute—thanks!Adaptador para batería 18650 para linterna Fulton MX-991Este adaptador…