Builders Transportation (BTS) based in Memphis Tennessee.Owned by Frank Phillips Sr and his 3 sons. Started in 1954. The USDOT number they got in 1954 is 0000531 which means only 530 trucking companies got a number before them. They list 244 trucks in their fleet.
A Penske truck pulling a flat. I guess it is gray. Kinda weird color to me.
The BTS Cascadia is nice, interesting history/info on them, too.
The gray Penske is odd, typically they're white or yellow, neat catch there, for sure.