Improve overall performance of ThinkPad systems by upgrading with additional memory. PC2-5300 memory offers maximum data transfer rates up to 5300MB/sec to help you increased performance of memory intensive applications such as streaming video, graphics and CAD programs. Adding more system memory is one of the least expensive ways to help boost overall notebook system performance and allows more multitasking which saves time and hassle. Compatible with ThinkPad R60, R61, R61e, R61i, SL300, SL400, SL500, T60, T60p, T61, X60, X60s, X60 Tablet, X61, X61s, X61 Tablet, X300, Z60m, Z60t, Z61e, Z61m, and Z61t systems. (1)Data transfer rates vary.