The Harken Standard Low Profile Cam Base Swivel is equipped with dual rows of Delrin ball bearings that allow for smooth swiveling, even when bearing high loads. It includes stand-up springs and a U-adaptor, making it compatible with a wide range of appropriately sized blocks. This low profile 205 version is ideal for deck-level installations and use with smaller blocks. Note: Delrin¨ is a registered trademark of E. I. du Pont de Nemours and Company or its affiliates.