The Parker 51 Mk.lll was only made for a relatively short time, from 1969 to 1972, so it is rather uncommon. This ballpoint version is distinguished from the Mk.ll version by the longer 'feather' section of the clip.
Finished in teal, the pen is in excellent condition. The click action mechanism works well and the pen has been fitted with a new Parker refill as the old one had dried through age. It is better to use a genuine Parker refills as they are better quality and longer lasting than the cheaper 'compatibles'.
The plastic case is new, it will serve well for transport and protection.