O-Ring 25.12 x 1.78 mm for SITA UV400 Centre Screw, UVOR2100, article 3865-1216. Data: inside diameter 25.12 mm, cross-section 1.78 mm. OEM reference: UVOR2100. Fits: UV400 / 400 series. Sleeve and chamber seals harden under UV, heat and chlorinated water. Replace them at every lamp or sleeve service; a re-used O-ring is the usual cause of a leaking sleeve gland. SITA HDPE series data: high-density polyethylene chamber for seawater and corrosive liquids, 1-980 m3/h, low-pressure high-efficiency or amalgam lamps with 9,000-16,000 h lamp life, 6 bar. Spare part for UV disinfection systems of S.I.T.A. srl, Genoa, Italy, which builds low-pressure, amalgam and medium-pressure UV units for drinking water, food and beverage, aquaculture, swimming pool, marine and wastewater duty (series AL, LCD / Rack LCD, AM, IT, 440, HDPE, SBT, SMP, SSD, TOC, GR and Pool).