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Product name: Lockwood 1800 series plate door furniture, internal plate with 70 lever and turn knob satin chrome plated (Part code 1904/70SC). Product characteristic:  Lockwood 1800 series plate door furniture consist of a brass lever on a brass base plate, which are satin chrome plated using a chrome 3 process. The lever handle operates a mortice lock mechanism.  The internal plate with 70 lever requires a matching external plate for a complete door assembly.  The plate includes a turn knob, which interacts with the mortice lock mechanism to lock and unlock the external handle.  The product can be used on timber or aluminium frame doors and has been approved for use on fire door assemblies as per AS1905.1-2015.