When I was ready to erect my tower, I realized I would need the better part of a 500' spool of coax (five lengths, close to 100' each). I had already used Davis RF's BuryFlex but, wasn't looking forward to the shipping cost from NH to WA. Comparison showed DX Engineering's DXE400MAX (link) appeared to be identical, with a lower per foot cost. Orders over $99 include ground shipping. RG-213's selling point is that it carries a Mil spec. DXE400MAX is actually better (more UV-resistant jacket, 100% shield, center conductor has more strands). Today, at under $2/ea, The RF Connection (link) has the best deal on silver-plated UHF male connectors.