Replacement battery for THT45. Specifications: 2600mAh, 3.7V, Li-ion. Compatible with: THT45, THT46, PQA824. Replaces: HT Instruments BAT45, HT Instruments BAT45N, HT Instruments YABA0003HT1. HT Instruments replacement battery designed for Equipment/Survey/Test Charger devices. Manufactured to exact OEM specifications.