Replaces OEM # L20M4P75, L20D4P75, SB11B79215, SB11B79216, 5B11B79217, 5B11B79218 Fits: LENOVO THINKPAD P1 GEN 4, THINKPAD P1 GEN 4 20Y3, THINKPAD P1 GEN 4 20Y4, THINKPAD X1 EXTREME 4TH GEN, THINKPAD X1 EXTREME 4TH GEN 20Y5, THINKPAD X1 EXTREME 4TH GEN 20Y6 Specs: 15.52V, 90.1WHR, 5805MAH, 4 CELL Brand New GreenTech replacement battery - 6 Month Replacement Warranty Each product has undergone rigorous testing to ensure the correct voltage, circuit protection, stable current, low self-discharge and CE / FCC / RoHS Certified for safety