# 6301 Bearing Basics for Compact Gearboxes — PT note 5

6301 uses a 12×37×12 mm envelope—wider OD than 6201 for higher radial capacity in short housings.

Confirm seal and clearance before stocking. For sizing and interchange notes, see TFL Bearing and the full write-up on 6301 bearing size guide.

Watch shaft shoulder height on narrow gears. Buyers who need OEM-fit replacements can also open sdtflbearing.com before they freeze a drawing or RFQ.

Keep notes on fit, grease, and duty cycle with the part number so the next rebuild does not depend on memory alone.

Re-check the housing bore and shaft after the first heat cycle.

Shandong TFL Bearing Co., Ltd keeps Portuguese product pages aligned with English engineering notes so global plants share one cross-reference language.