Crystal Glass Door Knobs Calzibeno antique glass door knobs interior are clear rosette glass shapes, with sturdy zinc alloy plates. The crystal door knobs are heavy duty and solid for long-lasting. These gorgeous diamond glass doorknobs are matte black finished and will surely add an elegant look to your home. Privacy Function The crystal door knobs with lock are ideal for interior room where privacy is needed, such as bedroom and bathroom. From interior, push pin button to lock, twist crystal knob to unlock. And you can use a hex key and any thin tool to insert the release hole to open the door from outside in emergency. Universal Crystal Door Knobs This black glass door knob fits with 1 3/8"(35mm) to 1 3/4"(45mm) doors, adjustable latch from 2-3/8"(60mm) to 2-3/4"(70mm). The crystal vintage door knob is single-cylinder reversible design, suitable for left or right-handed doors. Easy Installation Only need a screwdriver, you can easily install the glass