Replacement battery fits 8 TECPRO compatible models. Specifications: 1800mAh, 3.7V, Li-Polymer. Compatible with: NTi Audio Exel XL2, NTi XL2, NTi XL2 Analyzer, TW408, RENISHAW XR20-W, RENISHAW XR20 rotary axis calibrator and 2 more compatible models. Replaces: NTi 600 000 337, NTi LIP-009, RENISHAW A-9920-0330. TECPRO replacement battery designed for Equipment/Survey/Test Charger devices.