What is an aftermarket?

Aftermarket parts can be a sensible economy on simple, accessible components like belts, rollers, hoses and filters. They are a false economy on anything buried in the machine, because a cheap part that fails means paying the labour twice. Watch out for aftermarket listings that claim compatibility with a long list of numbers — those cross-references are the seller’s equivalence claim, not a manufacturer supersession, and they are not always right.