HM-30® standard 30″ hinged manhole ring & cover– cast ductile iron. Stock item. Locking or non-locking with hinged cover. Slip Resistant Surface with the LLLL® registered trademark. To prevent water infiltration, we furnish this item standard with our custom plastic plug, but gaskets for additional infiltration prevention are available on special orders. Standard type riser rings are not available, but you may use a concrete grade ring or Infra-Riser® to level the unit to grade from underneath the ring, both are stock items. Sold as sets but replacement covers and individual parts are available on special orders. Grates are not available for this item. H-20 traffic rated when ring is properly installed in reinforced concrete. Standard lettering available- Sanitary Sewer, Sanitary Sewer with customer ID plate area, Water, or Plain, No Lettering. Special lettering and non-standard LOGOs may be available on special orders. (we do stock many custom municipality letterings & LOGOs, email or call for details) See individual items for specific ASTM information. Made In USA. LEED® certifications available on request. Please use the Contact Form or call us to request info & submittal sheets. 1-800-258-2278 Toll Free or (972) 263-1360 DFW Local.