A fluorosilicone inner lining. Standard silicone is excellent with coolant, water and air but swells and breaks down in contact with petrol, diesel and oil. The fluorosilicone liner gives hydrocarbon resistance inside while keeping silicone's heat resistance and long service life outside. Ours are built to SAE J30 R6.

1 metre Fuel & Oil straights from 6mm to 63mm, fluorolined couplers from 6mm to 63mm in 20 lengths, 45 and 90 degree elbows from 6mm to 102mm, Long Leg elbows with 300mm legs from 13mm to 76mm, Classic Wrapped straights and elbows from 13mm to 51mm, and a fluorosilicone off-cut mixed box.

Yes - the fluorosilicone liner handles modern ethanol-blended petrol, diesel, oils and fuel vapour. This matters particularly on older vehicles: ethanol attacks unsuitable hose from the inside, so a line can look perfect externally while degrading internally and shedding material into the fuel system.

Yes, and it should be used there. A crankcase breather carries oil mist, which destroys plain silicone over time even though nothing liquid is obviously flowing. Breather and catch-can plumbing is one of the most common places the wrong hose gets fitted.

-60C to +180C, against -50C to +250C for plain silicone. The narrower top end is the trade-off for hydrocarbon resistance, and it is still far beyond what rubber fuel hose manages. It covers normal engine bay temperatures comfortably.

The fluorosilicone construction is not made in colours. In practice this works well: black on the fuel and oil circuits and coloured standard silicone on coolant and air makes the two instantly distinguishable, which is a real safety benefit when someone works on the vehicle years later.