I can't be 100% sure but either BB stub or BBB Stub nib. these are not very common for the era that they were in. it is in excellent working condition with no issues The Montblanc Meisterstuck 149 Fountain Pen with a Broad (B) Stub Nib is a vintage collectable item that exudes luxury and sophistication. Made by the renowned brand Montblanc, this pen features a beautiful 18K gold nib, adding a touch of elegance to your writing experience. The classic design and high-quality materials make this fountain pen a must-have for any pen enthusiast or collector looking for a timeless piece to add to their collection.
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