Mike I've had 2 lots from Pirtek, both reinforced with a steel coil, the first collapsed inwards restricting the flow, the secnd retracted all it's coils like a snake and then kinked! 2.5in is the biggest normal carpet cleaning vac hose in this country but I need 3in for my setup so what I'm going to do is use 2 90deg s/s elbows giving me an almost straight run and join them with marine exhaust hose