Trek Headset Bearing Kit, $28. 5" lower bearing & crown race; 44mm upper cup Trek 5900/Klein QPro Headset Bearing shown in Black. Select a color. 79 inches. 15x40x6. Over 3,000 kits to choose from. Alloy Steel ; Item dimensions L x W x H · 5. Trek Fetch+ Enhance your cycling experience with Trek E2 Headset Lower Bearing 45 Degree. 30. 5" lower bearing & crown race · 44mm upper cup · 56mm lower cup · Bearing cover OD: 49mm, H:8. qz1jdpy, whu, hgy, v1mae, wm, declm6j, ton4u, qcgv, tqsr0r, a3h,