Ruby Red Glass Knob Available in Three SizesColored hexagonal glass knobs have been widely used since the late 19th century in kitchens, baths, bedrooms and in every other room in the house. GK-107a - 3/4" DiameterGK-107b - 1" DiameterGK-107c - 1 1/4" Diameter (please note this item may take 7 to 10 days to ship)The nickle-plated bolt is inserted from the front through the head of the knob. We offer 3 sizes of knobs (sm., medium, large) and their corresponding handle. While this know is very durable and can stand up to heavy use, it is made of glass so special care needs to be taken when installing. Please hand tighten only. No power tools should be used.