The Kaw Valley Precision Thread Adapter 13.5x1 LH to 1/2x28 converts a 13.5 (LH) threaded barrel to a 1/2x28 (RH) barrel.
Not sure your application, but as a guide the AR-15 family says 24 ft-lb for muzzle devices, I would start around there. Crush washers are used for things that need to be timed, like a muzzle break, but not needed for things that don't have a specific orientation. Thread locker on a muzzle device is almost a holy war. If you use a suppressor, then yes definitely use thread locker, with no crush washer (they make timing shims for this application instead) and Rocksett is the recommended one there. If not, then the standard on an AR-15 is to use lubrication (believe it or not), Areoshell 64/33MS grease is the TDP recommendation.
We are not Kaw Valley Precision but an authorized retailer of their products. We will be happy to assist you with any questions or concerns, but it may be best to reach out to Kaw Valey Precision directly. Their contact information is
Phone: 816-919-1587
Email: info@kawvalleyprecision.com
The Kaw Valley Precision Thread Adapter thread patterns are listed next to the various models. We currently do not have a 5/8x24 to .578-28 adapter.