(Note: Measurements are outside max. dimensions unless stated otherwise).19th Century : Decorative knob with Tudor Rose petal design and bobbin edging.Top diam. 16mm. (5/8")Height 11mm. (3/8") + threaded shaft 14mm. (9/16")Collar diam. 11mm. (3/8")It is recommended that if selecting screw thread option, a pilot hole is drilled and pre-cut with a steel screw of slightly smaller size before screwing in the casting to avoid shearing.