Amazon.com: UpBright 5V AC Adapter Compatible with CAT 3.7V DC Rechargeable Battery LED Work Light WorkLights 962841 3.7 Volt CATwork CATLED Neiko 40464A RK-0421100 4.2V 4.5V Power Supply Cord Charger (NOT 12V) :
3.7 V Lithium Ion Battery Charger Adapter, Current: 1.4 A
3.7V Li-Po Battery Pack 240V Mains Charger
3.7V 1A Li-ion smart charger with 2.1mm plug
AC/DC UK plug Adapter Charger for 3.7v 4.2v 1S 18650 Lithium Li-ion Lipo Battery | eBay