Rail lacked any mechanism for mounting to rifle, was useless - Troy SOCC 5.56mm Low Profile BattleRail

I got my rail awhile back but was waiting for some free time to completely rebuild my upper and install it. I got everything put together and functioning, but when I went to mount the rail I found out that it had no mounting mechanism. There were no threaded holes, clamping mechanisms, etc that would lock it in place over the barrel nut. It just slides on and off freely, and has about 30 degrees of free rotation whenever it's in what should be the correct position. I thought I was going crazy and took it to 2 different gunsmiths trying to solve the problem, but both of them agreed that there was no way to mount it without doing some custom modifications.