A beaded joiner has a raised lip formed near each end, so the clip pulls the hose down behind a mechanical stop rather than relying on friction alone. That is what stops a joint blowing off under boost. An unbeaded joiner is smooth precision-machined tube - easier to slide hose onto, and it lets you set the hose position exactly, which suits coolant and low-pressure runs.

Beaded, every time. Charge air pipework sees pressure pulses and heat cycling, and an unbeaded joint can creep and let go, usually at full boost. Pair a beaded joiner with T-bolt clamps rather than worm drive clips and the joint will stay put. Save the unbeaded joiners for coolant, breather and low-pressure air.

It creates a three-way branch in a pipework run - taking a heater feed off a main coolant line, adding a bypass or breather takeoff, or splitting an air feed. Ours are available in 25mm to 102mm main bore with a 25mm spout outside diameter, precision-formed in T6063 aluminium with a polished finish.

The straight joiners, beaded and unbeaded, run from 8mm to 102mm outside diameter in 20 lengths from 50mm to 950mm - 22 diameters in each. T-pieces run 25mm to 102mm. Order by outside diameter, matched to the internal diameter of the hose that slides over it.

T6063 is a heat-treated aluminium alloy that balances strength, corrosion resistance and light weight, with a 1.6mm wall on our joiners and a rating of -40C to +220C. It will not rust, needs no coating, and sheds heat well - useful in charge air pipework where keeping intake temperatures down is the whole point of the intercooler.

You can cut the plain middle section of any joiner and deburr the ends. What you cannot do is cut near a bead without removing the bead itself, which defeats the purpose. Leave at least 25-30mm of tube beyond the bead for the hose and clamp to seat on. If you regularly need short pieces, the off-cut mixed box is a cheaper source than cutting up full-length joiners.