Yes, the maxupgrade sleds!
Use those, they work perfectly. In fact I have 4 of them for a new 2009 Mac Pro sitting on my desk. Paid around $45 a piece for them plus shipping to use 4 x WD velociraptors (if interested, PM me). DO NOT use those cheesey 2.5 to 3.5 addonics adapters, they only work for sata and only the 9.5mm drives, not raptors, not SAS drives.
Peace,
Noushy