Steel bar for mounting humbucker pole screws efficiently against the magnet.
Available in 49.2mm, 50mm and 52mm.

These are the small bras screws traditionally used to mount a humbuckers bobbins to their base plates.

Full threaded, slot head fillister pole bolts for humbuckers, available in Chrome, Gold, Black, Nickel and Cosmo, in M3 and 5 40 UNC threads.

Full threaded, Hex head fillister pole bolts for humbuckers, available in Chrome, Gold, Black, Nickel and Cosmo, in M3 and 5 40 UNC threads.

One of the "oddity" sizes of bar magnet - sometimes turn up in P90s, sometimes turn up in Mini-buckers, very rarely, even in full sized humbuckers. As always, worth checking the sizes to make sure this is the one you need.

These are the bar magnets commonly found in Gibson® firebird mini humbuckers - used as a magnetic pole within the bobbin, resulting in a very different tone.

Humbucker and P90 sized Bar magnets, available in Alnico 2, 3, 4, 5, 6, 8 and ceramic

62mm x 12.5mm x 3.2mm

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Humbucker and P90 sized Bar magnets, available in Alnico 2, 3, 4 and 5

58mm x 12.5mm x 3.2mm

Humbucker and P90 sized Bar magnets, available in Alnico 2 and Alnico 5

62mm or 58mm x 12.5mm x 3.2mm

Oversized bar magnets usually turn up in higher output pickups, and are a fantastic way to get a really unique tone.

Magnetic spacers are a novel little idea, and turn up sporadically on production pickups every so often. Essentially, they replace the inert maple or plastic spacers either side of a Humbuckers poles to alter the tone, usually by making a pickup more aggressive.