These are all pulled from HP SFF systems. These are very compatible part numbers.

These are packaged in a USPS Flat Rate BOX and will ship next business day!

10x Crucial/Micron 4GB 2666V ( CT4G4SFS6266.C4FJ )
4x Micron 4GB 1Rx16 2400T ( MTA4ATF51264HZ-2G3B1 )
6x Samsung 4GB 1Rx16 2400T ( M471A5244CB0-CRC )