This pen is now sold, but a very nice Mk. lll in black is available here.
The Parker 51 Mk. lV replaced the Mk. III in 1971. It is essentially a Mk. lll with a metal cap stud. Apparently there was concern about toddlers ingesting the pearl cap stud on the earlier pen. Production of the Parker 51 ceased at the end of 1972, although they continued to be sold for a while afterwards. This pen is the last of the 'true' Parker 51s.
The pen is a 'Custom' version featuring a rolled Gold cap. Finished in red, actually more of a maroon colour, the pen is in first rate condition showing no scuffs or other usage marks.
It has been fully serviced and tested. The 'Aerometric' filling system works well and the 14 Ct. Gold nib writes with a smooth and consistent line, perhaps a tad on the fine side of medium.
The pen is presented in a haerd Parker case which is also in excellent, clean condition.
The Parker 51 is the most successful pen ever made and has gained a reputation as a stylish, trouble free, practical pen. It would make a first class every day writer and has a great deal of prestige.