Robustline Door Chain Guard Lock with Double Locking System, BT-0010C, Stainless Steel, Brass Plated

The Robustline BT-0010C Door Chain Guard Lock (brass plated) is a secondary security hardware device designed to reinforce your existing door locking system. At its heart is a durable stainless steel mechanism that ensures structural integrity, overlaid with a brass plating that offers an attractive finish and additional surface protection. This model supports a double locking system-that is, a primary chain latch for limited opening and a secondary locking element (such as a sliding bolt or pin) that engages when the chain is in use. The dual mechanism increases resistance to forced entry by introducing redundancy: even if the chain is stressed, the secondary lock provides an additional barrier. The brass-plated finish gives the device a warm, golden appearance that complements traditional, vintage, or classic décor styles. It visually aligns well with brass handles, hinges, and other brass hardware. At the same time, the plating acts to reduce direct exposure of the metal core to moisture or corrosion, enhancing the longevity of the surface. When installed, this chain guard allows the door to be partially opened (for ventilation or identification) while maintaining a safety barrier. The design is compact and low profile, intended not to interfere with everyday door operation or aesthetics. Mounting is surface-based: one component secures onto the door, while the chain bracket (or keeper) mounts to the door frame (or the reverse, depending on door swing). Screws (or fasteners) are provided for installation. The device is typically usable on both inward- and outward-swinging doors, depending on mounting orientation and alignment.