2GB KIT (2 x 1GB) For Sun Ultra Series 20 M2 Workstation 24. DIMM DDR2 ECC Unbuffered PC2-5300 667MHz Dual Rank RAM Memory. Genuine A-Tech Brand. 2GB KIT (2 x 1GB) DIMM DDR2 ECC Unbuffered PC2-5300 667MHz Dual Rank RAM Memory Genuine A-Tech Memory Lifetime Warranty Toll Free Technical Support 1-866-557-4527 Designed For Sun Ultra Series. (See Compatibility List Below)