I am fortunate enough to be able to offer you this difficult to obtain cable. Now that it has become a rarity in the radio and TV industry. I was able to find a company, which is still producing it for me. This cable is particularly suited for use by radio amateurs because it offers a good alternative to the open line for use with low to medium power outputs. OK, you can still find the well-known "WIREMAN" open line, but this is rather obtrusive, somewhat heavy, and very much overkill for use with 100W output. Most amateurs using parallel line fed antennas don't use a PA because suitable antenna tuners are rare, and very expensive if you do happen to find one. This makes the use of windowed ribbon cable an all the more interesting alternative.
Polyethylene solid dielectric in black. Polyethylene has excellent weathering properties compared to PVC.
Temperature range: - 40C to + 60C
Dimensions: 9.8mm wide - 2.5mm thick
Weight: approx. 30g /m
Velocity-factor: approx. 0,82
Conductors: approx. 0,81mm (AWG20) diameter, Litze wire comprised of seven bare hard drawn copper wires ,each of 0.32 mm diameter. Power rating: approx. 500 watts
You can find a suitable T- insulator at "insulators"