IB51325 IBM Laptop DC Power Jack for Thinkpad 600E, 600X, A20, A21, A22, A30, X20, X31, X60, X61, R40 Series NEW DC Jack Center pin diameter: 2.5mm IBM Laptop DC Power Jack for Thinkpad 600E, 600X, A20, A21, A22, A30, X20, X31, X60, X61, R40 Series NEW DC Jack Center pin diameter: 2.5mm