The SRLRB is a long rail with 2 screws and nuts. It can be mounted the base bracket of a PowaBeam spotlight or any bracket with a flat surface that can handle screws and the weight.
It is a longer version of the SRWTR made specifically so you can select a mounted location that helps with balancing the spotlight. When a thermal is mounted on the top of a spotlight using the Rimtop mount the weight can be set forward, in turn unbalancing the weight on top which makes the remote lean forward.
This rail gives you the ability to clamp the light and thermal in a balanced location.
Note: as shown in the images, you will have to drill 5mm holes to mount this product.