The ATM HS-1 is a shelter hatch designed for use in protected spaces. According to the product information provided by Shelter Shop, the hatch is designed to meet and, in some parameters, exceed the Finnish norms for S1 shelters. The ATM HS-1 combines blast resistance with gas-tight sealing and is designed with an inward-opening configuration. Its construction and locking system are intended for installation in shelter structures requiring protection against blast-wave pressu