Vintage detachable collar, Metropole Brand, Marconi style, sold by Buckley & Prockter of Mumps. Probably early 20th century (Edwardian or shortly afterwards).
You will need a pair of collar studs to fix this collar to your tunic shirt. These studs are NOT included, but are available separately (the stud in the pictures is just for display).
Size: Collar size 16 (to fit shirt size 15.5).
Condition: Vintage collar, around a century old, but in excellent condition. Laundry marks of several previous owners on the inside.