The first two guides in this 1966 group appear to be variations on a theme, and may or may not have the same part number. Availabilty dates are a mystery as well.
Above is an Atlas 1570-8. It's pretty badly chewed up, but is the best example in the bunch.
Here is a very similar guide, but is it an Atlas and does it have the same part number?
Here are both guides side by side.
Here is the Custom Slot Car Products Co. guide, part number 2003. Looks like it can be used as a normal or leading post guide simply by reversing the braid and plug.
Looks like three guides complete for two bucks! Such a deal!
Here's a variation I've not seen before; a Dynamic 658 guide molded in gray. The only colors I've seen in Dynamic packaging are black and white.
Another Dynamic 658 molded in orange.
Two more variations. First, an MPC 429 molded in black. All others I've seen are white.
Second, a Revell 3508 molded in gray. All others I've seen are black. The blade is very short, having been trimmed (perhaps for home track use) by the previous owner.
