Hamilton Kent | 7,609 followers on LinkedIn. Sealing Your Connection | Since 1943 Hamilton Kent has been recognized as one of the leading international manufacturers and distributors of a full range of rubber gaskets for manholes and all types of pipe materials. Over the years, HK has developed numerous flexible pipe-to-manhole connectors, both cast-in and mechanically-installed, for ensuring watertight underground infrastructure. Recently added to HK’s product line is The Lifespan System, a watertight, corrosion-proof rubber manhole frame with a lock-down cast iron or composite cover, specifically designed to eliminate water inflow and infiltration through the cover or chimney area.