Replacement battery fits 7 Wayteq compatible models. Specifications: 800mAh, 3.7V, Li-ion. Compatible with: X820, X850, Curtis GPD430, Curtis GPD 430 GPS, MLS Destinator Talk&Drive 43SL, MLS Destinator Talk&Drive 43SL A and 1 more compatible models. Replaces: WayteQ 554844P. Wayteq replacement battery designed for GPS/Navigator devices. Dependable performance you can count on.