K-series OEM LSD
Bearings spin smoothly
$440 shipped (that also includes the paypal fees)
Buy with confidence! My vouch thread on Honda-Tech: http://htarchive.org/showthread.php?t=993363
Honda-Tech member since 2002!

RSX guys: this will fit your transmission, you'll just need to add the Honda VSS ring. You can remove the VSS ring from your open diff, or you can order a new one from Honda (they're about $40 new).
Here's a video to give you an idea of how easy it is:

 

will this fit k20z1 05 rsx type s trans?

 

Sold to Panchitobuilt90 on K20a dot org
Thank you for looking