US Patent 11905161 Form-coded underground storage tank filling port

A form-coded collar assembly that is configured to be attached around a filling pipe extending into an underground fuel storage tank and comprises a radial lip defining an opening at its open end, and a system having a plurality of such form-coded collar assemblies. The collar assembly has a base plate with a hollow center comprising a greater footprint than the filling pipe; a form-coded collar that corresponds to a substance contained within the underground storage tank; and a sidewall extending between a user-facing surfaces of said base plate and said form-coded collar.