Straight rubber radiator hose from 5mm to 102mm internal diameter, plus moulded 45 and 90 degree radiator elbows from 10mm to 76mm with 150mm legs each side. All EPDM to SAE J20 R3, glycol rated for standard antifreeze mixes.

Order by internal diameter, matched to the outside diameter of the pipe stub the hose slides onto. Measure the pipe itself with vernier callipers rather than measuring the old hose, which stretches in service and always reads larger than the pipe it was fitted to.

EPDM rubber to SAE J20 R3, -30C to +120C, glycol rated. That is the specification of virtually all original-equipment coolant hose. It is not suitable for fuel or oil - hydrocarbons attack EPDM and it will soften and swell.

Use a moulded elbow for any real change of direction. Bending a straight hose closes up the bore, restricts flow and creates a stress point that will split eventually. The moulded elbows have 150mm legs each side, 300mm total, so there is plenty to trim to fit.

Squeeze it. Hard and brittle, or spongy and swollen, both mean it is done. Look for surface cracking when you flex it and crusty residue or staining round the clips, which indicates seepage. Replace on condition - coolant hose failures are sudden and always inconvenient.

Yes, if you have the system drained. They are the same age and have had the same heat cycling, so the second will follow the first within a short time. Doing both while the coolant is out saves repeating the whole job for the sake of one hose.