DETAILS: NOTE: cap top lip shows a custom small "notch" underneath the clip (last pictures). In my opinion the cap is original of the 51 line with the referred notch having been made (in the past) for another type of clip which may have been fitted in a previous cap or pen version (?). This style of cap really exists with "51" pens and is relatively scarce. Wonderful vintage Parker "51" model MK I from 1948 production (small "8" engraved on the barrel lip near clutch ring - visible in pictures). In nice Dove Grey colour Lucite plastic barrel and grip section. 1/10 14K Gold Filled cap with "Wavy Lines" in pairs alternating with pairs of fine parallel lines engraving with smooth polished and engraved lip band. Gold plated clip and gray mother-of-pearl conical cap jewel. Old style Vacumatic arrow clip with Blue diamond on top. Vacumatic filler with amber plastic plunger hidden under a blind cap. 14K/585 solid gold nib, probably "F" fine tip (looks so, not marked outside). The barrel lip is engraved in two lines under the clutch ring: PARKER "51" - MADE IN U.S.A. - 8 (see pictures). Total length (cap closed): 13,9 cm. Made in USA. Perfectly clean and shiny ! No case or instructions supplied, sorry. All original and authentic. Please consider the pictures as part of the description as they show the exact item that will be purchased. CONDITION: Excellent vintage overall - indeed very nice, very gently used with insignificant wear marks and no flaws. Working 100%. Plastic barrel and section very polished and shiny with very few microscopic marks only remaining after buffing, no obvious marks, dents or scuffs. No cracks. The engravings near the clutch ring are perfectly crisp, fully readable ! GF cap with no wear or visible marks overall. No deformations. No dents, no dings, no cracks. No scuffs and no oxidation. Clip is nice and excellent, however with slight plating wear on arrow point and base ring edges, still acceptable. MOP jewel perfectly conserved and shiny with no ageing or yellowing. Clip is perfectly straight aligned and adjusted firmly to the cap surface. No repairs. No deformation to cap and barrel. Cap closes smoothly and holds tight both closed and posted. The nib is perfect too, no marks and no deformations, with plenty iridium. Tuned. Flexible and smooth spring action of filling system push button. Filling up easily, holding good quantity of ink. No leaks or blots. Writing perfectly and smoothly (tested). No personal engravings. In perfect working condition. PACKING & SHIPPING: Package Includes: Item as described and carefully packed with Catawiki Invoice. I will post Item by Registered Mail with Tracking Number (to be provided on Order page after shipping).