These knobs are unsprung so must be fitted with a heavy duty double sprung tubular latch. Finish: Antique Brass Dimensions: 50mm Knob Diameter, 76mm projection, 70mm Rose Diameter Ensure latch chosen provides sufficient back set to distance the knob from the door frame On fire doors we recommend 4" Heavy Duty latches with mortice door knobs Supplied & sold in pairs complete with fixings Founded in 1989, Atlantic Handles has spent years proving themselves to be a simple, honest on-time quality service for construction and ironmongery. The Old English collection consists of various older traditional designs but with the latest manufacturing innovations to ensure the products are of an exceptionally high quality and available in several impressive finishes. This 50mm Round Rose Round Reeded Mortice Knob from the Old English collection comes in a Antique Brass finish that matches perfectly with other Antique Brass products from the Old English collection, making it an ideal choice for completing your door in a uniform finish and style.