The Esterbrook 'J' double jewel series was made in three sizes the 'J', the 'LJ',  this pen, was about the same length but slimmer, and the 'SJ' was shorter.   

Introduced in 1948, the earliest pens, such as this example, didn't have the 'R' registration symbol on the imprint, this is a 1940s pen.

The pen is finished in 'Foliage Green', a 'Fern Green', which was a few shades darker was also made, this is one of the much brighter pens.  It has an excellent surface with a brilliant shine and a clear barrel imprint.  The 'double grooved design of the clip is carried through to the cap band and the filler lever, all in good condition.  It is a 'double jewelled' pen, with a black stud at the barrel and cap ends.

The pen has been restored and tested and is now in excellent working order. The nib is  engraved 'Esterbrook 9128',  The '9' series nibs were known as the 'Master Point' nibs and are all tipped with Iridium. they were originaally much more expensive than the standard 'Dura' nib.  The 9128 is listed, in the comprehensive Esterbrook nib code document, as a 'Extra fine flexible for fine penmanship or Pitman's shorthand.'.  This was a rapid writing system that used symbols formed from fine and slightly wider lines so a specialist nib was essential.

At 13 cm. capped and an impressive 15.5 cm. with the cap posted, this is a long and very well balanced pen with a satisfying solid feel.  The stainless steel trim, thick celluloid, and good build quality make the Esterbrook LJ very attractive, practical  and durable pen.