Contain three parts ①internal lid, ②corbel, and ③base. The internal lid is locked onto the corbel tightly to prevent the water penetration. The opening diameter of corbels is 31 1/2". The base is connected with oil tank manhole via round upstand flanges.

SSR 125090  Base 48"x20"

SSR 125091  Base 48"x20"，conductive

SSR 127090  Base 48"x28"

SSR 127091  Base 48"x28"，conductive

SSR 129090  Base 48"x36"

SSR 129091  Base 48"x36"，conductive

SSR 145090  Base 55"x20"

SSR 145091  Base 55"x20"，conductive

SSR 147090  Base 55"x28"

SSR 147091  Base 55"x28"，conductive

SSR 149090  Base 55"x36"

SSR 149091  Base  55"X36"，conductive

SSR 165090  Base 63"x20"

SSR 165091  Base 63"x20"，conductive

SSR 167090  Base 63"x28"

SSR 167091  Base 63"x28"，conductive

SSR 169090  Base 63"x36"

SSR 169091  Base 63"x36"，conductive