24x 21700 Battery. Only RBC-58ACR has Battery Tester （ Battery Size：AA AAA Battery Case with Tester ）. KIWIFOTOS RBC-58ACR Battery Case with Battery Tester is an organizer designed to accommodate up to30 pcs AA batteries, 18 pcs AAA batteries and 10 pcs c oin batteries (I tem on s ale is the c ase ONLY, batterie s are N OT i ncluded ).
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