Trek E2 Headset Lower / Upper Bearing 36-Degree 51 mm x 40 mm x 7 mm 2022 Ships within Australia In stock. Available via Click and Collect or Buy Online Share Loading Facebook Like button... Trek E2 Headset Lower / Upper Bearing 36-Degree 51 mm x 40 mm x 7 mm 2022 Ships within Australia In stock. Available via Click and Collect or Buy Online Share Loading Facebook Like button...