Four options: SRAM; SRAM X-0; Shimano XTR, XT, LX, Ultegra and Dura-Ace; Shimano Deore, 105 and Tiagra / All available in 10mm axle version for an additional £5 / Contact: Rolf’s Pukka Parts 01753 646 739

If you’ve seen the rear mech reinforcers on Specialized bikes but can’t get hold of one, then North Shore Billet should be your next port of call. Machined from 6061 T6 aluminium, the Hanger Banger protects and reinforces the rear mech by forming a parallelogram with the mech and hanger. It’s easy to fit and it is guaranteed to extend the life of your rear mech and hanger, even if it makes it more difficult to remove the rear wheel. Pricier than the Specialized unit, but easier to get. Just make sure that you buy the correct model to match your mech.