CPC Subgroup
G03B 21/18 Fire preventing or extinguishing
Full Title
Projectors or projection-type viewers; Accessories therefor (devices for changing pictures G03B23/00) > Details > Fire preventing or extinguishing
G03B 21/18 Projectors or projection-type viewers; Accessories therefor (devices for changing pictures G03B23/00) > Details > Fire preventing or extinguishing