1st Generation 70s Remo RotoTom Rail Track Mount for Roto Tom Drum - 23 1/4”

Other than one photo, I’ve never seen this style of Remo Roto tom track. Based on my research, its prior to the 1980’s second generation Roto tom drums, Im guessing its 1970’s or earlier. Could be a prototype? The rail is 23 1/4” long x 3/4” wide x 1/2”. Each tightening knob works fine. Each knob appears to be painted shades of blue. Each hole on the aluminum rail is approximately 3/8” diameter. The two outer holes and middle hole have threads that are worn. (Threads presumably help grip the rod you would insert). The other holes appear smooth. A head to a rod broke off while attached to the middle hole - I left in. Please refer to the photos which are considered a part of the description.

* in other listings are a 6” and 8” Roto tom drum.