Modular cold rooms are built from insulated sandwich panels. A cam lock has a rotating hook embedded in the edge of one panel and a matching pin in the next. When an installer turns the hook with a hex key through a small access hole, it catches the pin and draws the panels together, compressing the joint seal.
This gives a tight, consistent joint without screws through the panel faces, and it allows panels to be taken apart and rebuilt if the room is moved. Tongue-and-groove edges help align panels and lengthen the path for heat and moisture through the joint.
Joint quality decides how well a cold room performs. A loose or unlocked cam, a missing gasket or an unsealed gap lets humid air into the joint, where it condenses or freezes, leading to ice lines, damp panels and higher running costs. After installation, all access holes should be capped and joints sealed. Note that walk-in cold rooms are a separate product category from plug-in cabinets.