Practical bearing sourcing guides written by the people who quote. No SEO filler — these are the questions we actually get from buyers, answered the way we answer them in email.
6204 (20×47×14 mm) is one of the five most-used bearings worldwide. Dimensions, Cr/Cor ratings, ZZ vs 2RS seals, C3 clearance, cross-reference by brand and what to verify before ordering.
Clearance is the internal play between rings and balls — and it shrinks under interference fit and heat. Why electric motors default to C3, when C4 is right, and the mistakes that kill bearings early.
What every suffix and prefix means — seals, clearance, precision, cages, contact angles — with brand-by-brand equivalents for SKF, NSK, NTN, FAG and KOYO.
Z1–Z4 is the vibration acceleration scale — the higher the number, the quieter the bearing. dB limit tables by bore size, how to pick a grade, and how to write inspection terms that hold up.
Precision controls tolerance and runout — a P5 costs multiples of a P0. Grade system, old-code mapping, ABEC equivalents, and the four traps when buying precision bearings.
Measure d, D and B to build a candidate list, then verify bearing type, suffixes, ring features, fits and operating conditions before replacement.
The 608 is the most common miniature bearing in the world — skateboards, fans, small motors, 3D printers. But the ZZ (metal shield) and 2RS (rubber seal) variants behave very differently. Here's how to choose.
The 6200 series is the most-cross-referenced standard bearing in the world. If you buy deep-groove bearings, you will encounter it. Here is what to check before you place an order.
Custom bearing quotes take longer than standard ones, but most of the delay comes from missing information — not manufacturing. Here's a checklist that gets you a real quote in days, not weeks.