Watermans Ideal No.4 Keyhole Nib. (Fine Flexible) N536 £55.00 Out of stock. Summary; Manufacturer: Watermans Designation: No.4. Origin: UK. Material: 14ct Gold. Dates from (approx): 1940. Overall Length: 33mm. Writing Width: Fine Flexible. Notes: All sizes and measurements are approximate. Any replacement nib may need some adjustment when fitted to the pen. We can fit this nib as part of a service on your pen, email us for details. Postage in the UK is free on this item!