Shimano, BB-UN300 Bottom Bracket 68x122.5mm w/o Bolts FREE shipping within Australia over AU$199.00 In stock. Available via Click and Collect or Buy Online Share Loading Facebook Like button... Shimano, BB-UN300 Bottom Bracket 68x122.5mm w/o Bolts FREE shipping within Australia over AU$199.00 In stock. Available via Click and Collect or Buy Online Share Loading Facebook Like button...