Bottom Brackets

Shimano's BB-UN55 Square Spindle Bottom Brackets are the unofficial standard for English-threaded cartridge bottom brackets. Quality, value, and durability come together to keep you cranking for many, many miles. - Fits JIS Square-Taper Cranksets - Hollow spindle - Crankarm fixing bolts not included

- One-piece bottom bracket cup set - Bearings included - Fits smaller american juvenile/youth sized BB - Shell: 65mm - Cup Material: Steel - Weight: 173 grams

Box Two 24mm External bottom brackets feature cold-forged, CNC-machined alloy cups, dual-labyrinth bearing covers, and precision sealed bearings. They are the perfect match to Box Three, Four cranks, and the ultimate upgrade to the budget BBs sold with most cranksets. Box Two, 24mm External Bottom Brackets, are designed to fit all 24-millimeter crank spindles and frames with 68 or 73 x BC 1.37-inch bottom bracket shells. Features: - Stable Outboard Bearing Position - Precision Abec-5 Sealed Bearings Compatibility: - Compatibility: Box Three, Box Four, Shimano HollowTech II, RaceFace X-Type - Material: 6061-T6 Aluminum - Shell Width: 68mm/73mm - Spindle Type: 24mm - Thread: 1.37 Inch x 24 TPI - Weight: 105 grams / 3.7 ounces Specs: Process: CNC-Machined Cups Material: - Cups: Alloy - Sleeve - ABS Plastic Finish: Anodized Spindle Type: 24mm Shell Width: 68/73mm Thread: 1.37 Inch x 24 TPI (English) Compatibility: - Shell: BSA (Euro) Threaded - Spindle: Box Three, Box Four, Shimano HollowTech II, RaceFace X-Type Weight (+/- 5%): 105 g / 3.7 oz

- Forged steel body - Alloy cups - Chromoly spindle - Sealed bearings - Interface: English - Spindle Type: Square Taper JIS - Weight: 290-300 grams

- Steel body - Steel cups - Chromoly spindle - Sealed bearings - Interface: English - Square Taper JIS - Weight: 305-320 grams

- Bottom bracket for one-piece crank - Sealed mechanism - 24 TPI - Spindle Type: One piece - Cup Material: Steel - Weight: 310-315g - Cup Type: Press Fit - Cup OD/Bearing OD: 51mm

- Replacement fat bike bottom bracket with square-taper chromoly spindle - Sealed bearings - Steel shell and cups - 120mm shell width - 180mm spindle length - 1.37" x 24T English thread

- With plastic washers - Shell: 8mm Allen head axle bolt

Forged and CNC machined AL6061 cups - Double sealed replaceable bearings - Fits 68mm and 73mm shell widths - 1.37" x 24T English thread - Alloy spacers included for chainline adjustment - Anodized and laser etched finish

- Standard JIS square taper with steel cups, retainers, lockrings, CrMo spindle, shield included - Formerly called CBB-ST, renamed CBBF

- For 19mm crank spindles and Euro bottom bracket frames - Sealed quad bearing design with alloy cups - Shell: Euro - Interface: English - Spindle Type: 19mm

- Compatible with both American and Mid style BB shells - 6061-T6 full CNC alloy construction - Anodized surface finish - Weight: 255g - Cup Type: Press Fit - Cup OD/Bearing OD: 41mm or 51mm