I fitted my freight cars w/ the magnetic working air hoses. The hose material is black Larva Lace hollow tubing (fly fisherman use this, so many outfitters have it; $2-3 will get you more than enough). As to the glad hands, there are a variety out there, but I prefer the brass ones from Protocraft (PC-1203a) - about $5/pair. I ordered the Neodymium magnet discs from K&J Magnetics - 1/32” thick x 1/16” diameter. I attach them with a drop of CA and they've always held. I do not worry about polarity. Depending on how they are fitted to the car, you may need to nudge them a bit with your fingers to connect - which is fine with me as it slows you down during operating sessions.
I forgot - the Protocraft glad hands come with hose material with a matte finish - perfect cosmetically, but they may be a tad too short.
...gregg
