3 x AAA Battery Holder with On/Off Switch and 2-Pin JST : ID 727 : $1.95 : Adafruit Industries, Unique & fun DIY electronics and kits
Varta CR 1/2 AA 3V Lithium Battery, Capacity: 950Mah, Voltage: 3.0 V
AA vs. AAA Batteries: What's The Difference? (Explained) – All The Differences
12-Pack Rechargeable AAA Batteries Pre-Charged, NiMH 1.2V 600mAh Triple A Solar Batteries for Solar Lights and Universal Household Devices, Recharge up to 1200 Cycles, UL Certified - 12 Count 12 Count (Pack of 1)
Battery Ni-MH 2/3AAA 100mAh 1.2V for SOLAR Lights Decorative Micro AAA Battery | eBay