Merrill's Pitless Kits come in MCK520 and MCK620 series. The certified watertight pitless kits feature a positive mechanical seal with a large, thick O-ring seal. The kits allow full diameter access to well and include discharge hub clamps around casing with two stainless steel or galvanized u-bolts. The three-part kit uses existing casing and, with its support bars, holds a substantial amount of weight. Merril