This is the JMI Reverse Crayford Focuser 2" with 1.25" insert. It has ball bearings and is very smooth. I purchased this for a project that I am not going to finish so it is up for sale. I paid $99.00 for the focuser and 19.95 for the insert plus shipping. It can be yours for $95.00 shipped to your door via Priority Mail.
Thanks for looking,