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Adeka delivers reliable hydrophilic rubber waterstop systems designed for sealing construction joints, pipe penetrations, tunnels, and below-grade structures. Since 1977, Adeka’s UltraSeal line - including MC‑2010MN, KM‑3030M, MC‑2005T, KBA‑1510FP, and P‑201 sealant - uses double‑locking compression and moisture‑activated expansion to resist high hydrostatic head pressures. Adeka’s P‑201 putty‑like sealant complements preformed options, adapting to rough or irregular substrates while curing into a durable, watertight barrier. Globally rooted in the century‑old Adeka Group, the brand brings advanced hydrophilic technology from Japanese R&D to U.S. projects.