IBM 16V 4.5A 5.5*2.5mm ac adapters compatible models:

1400 Series ,1500 Series ,172x Series ,235 Series , 240 Series , 290 Series

310 Series , 340 Series , 365 Series , 370 Series , 380 Series , 600 Series

701 Series , 770 Series , A21 Series , A22 Series , A30 Series , A31 Series

E530 Series ,i1100 Series ,i1200 Series , i1300 Series , i1400 Series

i1500 Series , i1700 Series , i1800 Series , R30 Series ,R31 Series

R32 Series , R50 Series , R52 Series , S30 Series , T20 Series , T21 Series

T22 Series , T40-2373 , T41 Series , X20 Series , X41 , X41 Tablet PC Series

X41 Tablet 1866 , X41 Tablet PC

For IBM WorkPad z50 Series

For IBM Workpad z50-2608