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18650 battery chargerNitecore and Xtar make the reliable chargers. A four-slot charger with individual bay monitoring costs less than replacing batteries from bad charging.
1,000+ lumen EDC lightFenix PD36R, Olight Warrior, and Streamlight ProTac are the three brands with consistent QC. Turbo mode + low mode is the useful combo.
Rechargeable headlampPetzl Actik and Black Diamond Spot are the two headlamps that don't fail at critical moments. USB-C charging is worth seeking out.
Pocket EDC lightA sub-100-lumen pocket light you actually carry beats a 2,000-lumen light left in a drawer. Fenix E18R or Olight i3T are sensible picks.
Holster + pouchA kydex or nylon belt holster for your main carry light keeps it accessible and protects the lens. Fits most 1-inch tube lights.