RBC Aerospace Bearings offers a full line of Mil Spec standards and many specialty and custom airframe control needle track rollers to the aerospace industry and all major OEM specifications. RBC airframe control needle track rollers conform to SAE-AS39901, formerly MIL-B-3990. These bearings are designed for use as track rollers with a very thick outer ring to withstand heavy rolling loads. They are corrosion protected, grease lubricated, sealed, or unsealed.