1. Product Overview 4T-30311D is metric single row separable tapered roller bearing, D suffix represents 24°-32° steep large contact angle, complete matched cone and cup set with overall dimension 55×120×31.5mm. Large conical contact angle greatly upgrades unidirectional axial thrust bearing capacity while maintaining strong heavy radial load performance, perfectly fit equipment enduring huge axial impact during operation. Separable inner cone and outer cup structure