This IBM 02k6699 Notebook AC Adapter / power Charger, is compatible with the following IBM Thinkpad laptops:

IBM Thinkpad A series:
A20, A20E, A20M, A20P, A21E, A21M, A21P, A22E, A22M, A22P A30, A30E, A30M, A30P, A31, A31E, A31M, A31P A2628, A2629, A2633
IBM Thinkpad R series:
R30, R31, R32, R40, R50, R51, R52
IBM Thinkpad i series:
i1100, i1200, i1210, i1211, i1214, i1217, i1230, i1234, i1237, i1241, i1250, i1251, i1254, i1257, i1260, i1264, i1267, i1271, i1300 type 1171, i1310, i1320, i1321, i1330, i1334, i1335, i1337, i1340, i1351, i1361, i1370, i1374, i1375, i1377, i1381, i1391, i1400 type 2621, i1418, i1420, i1421, i1422, i1440, i1441, i1442, i1460, i1480, i1482, i1483, i1490, i1492, i1500 type 2621, i1540, i1541, i1542, i1560, i1562, i1572, i1592, i1700, i1720, i1721, i1750, i1800
IBM Thinkpad S series:
S30, S31 series
IBM Thinkpad T series:
T20, T21, T22, T23, T30, T40, T41, T42, T43, T51 series
IBM Thinkpad X series:
X20, X21, X22, X23, X24, X30, X31, X32, X40, X40 X2660, X2661, X2662 240 240X
IBM Thinkpad series:
1200 1300 240,310,380,390,560,560E, 560X, 570, 600, 600E, 600X,770,770E, 770ED, 770X, 770Z