Input: 100-240V 50/60Hz 2.5A Output: 20V 8.5A 170W Connector: 11mm*5.5mm Square Port Size: 5.51 x 3.07 x 0.87 Inch Compatible with： ThinkPad P ThinkPad P1, P1 Gen 3 20TH 20TJ, P1 Gen 4 20Y3 20Y4, P15 Gen 1 20ST 20SU, P15 Gen 2 20YQ 20YR, P17 Gen 1 20SN 20SQ, P17 Gen 2 20YU 20YV, P50, P51, P52, P53 20QN 20QQ, P70, P71 20HK 20HL, P73 20QR 20QS ThinkPad T T15g 20UR 20US, T15g Gen 2 20YS 20YT, T431s, T440, T440p, T440s, T450, T450s, T460p, T540p, T550 ThinkPad W W530, W540, W541, W550s， X240, X240s, X250 ThinkPad X1 Extreme Gen3 20TK 20TL, X1 Extreme Gen4 20Y5 20Y6 ThinkPad E ThinkPad E440 E450 E555 ThinkPad S ThinkPad S431, S440, S531, S540 ThinkPad L ThinkPad L450AIO 3AIO 300-22ACL, AIO 300-23ACLLegionLegion Y520, Y520-15IKBN, Y530-15, Y540-17, Y720, Y720-15IKB, Y730-17ICH 81HG, Y7000, Y7000-2019 1050, Y7000P, R720, Y900, Y910, Y920 AIO DesktopAIO B40 B40-30 C40 C40-05 C40-30 C50-30 E50-05 S500zC C355 C455 C560 IdeapadY700, Y720-15lKB IdeaCentre A A540 A740TIOYINZ Step 1: check the following three items to determine if there is something wrong with the charger: 1. Check if the AC socket is powered on. 2. Connect the charger to the AC power supply and the device to see if the device LED is lit, or to see if the settings start properly. 3. Check whether the indicator light of the charger is on, or check the DC plug of the charger with a multimeter for voltage. Step 2: make sure you can buy a matching charger by comparing the following three aspects: 1. Applicable brand and output voltage. 2. [color], [shape], [outer diameter, inner diameter or DC tip size] of the DC plug. 3. The output current and maximum output power of the charger. (generally not lower than the power of the original charger). After comparing the above three aspects, you can order the charger directly.