Typically 250K pots are used für Single Coil Pickups aus 500K pots für Humbucker pickups. The bigger the resistence value, the brighter the sound will be/ less highs will bleed off. 1MEG can be used to make humbuckers sound brighter. Taper:The taper of a pot refers to the way its resistance changes as the shaft is rotated. A linear taper pot will work in a linear way related to shaft rotation. As the human ear is not linear in response to increasing Volume an audio or logarithmic pot will work best für Volume applications.Shaft:A split, knurled shaft will hold most knobs. Sometimes the knob is mounted using a set screw. You should order a solid shaft pot, or align the set screw mit the split für correct mounting.Bushing:The Standard bushing Durchm.is 3/8" or 9,5mm, used in most made in USA guitars. Another industry Standard is M8, as used by guitar builders outside of the USA. When space is limited mini pots are used mit a shaft Durchm.of 7mm. The Standard bushing length is .375" für inch type pots und 10mm für metrisch type pots. Using two nuts it is very easy to set the correct bushing length für knob placement. Specially für Pickguard (ST, PB) or Control Plate mount (TE, JB) the .250" short bushing will fit perfectly using only one nut.For use mit a Thick or carved top (LP USA) you should order a bushing length of .750".CTS is (and has been since the 50's) a factory Standard für most USA brands like Fender und Gibson. Alpha is a good Alternative, nowadays used as a factory Standard by Ibanez, Epiphone und Squier.