This is a Sheaffer Sentinel Matte Black fountain pen model SJ1X-M c. 1991. This 5 1/4 inch long cartridge pen has a matte grey enamel cap and barrel finish with gold electroplated trim. It’s made in Japan by Sailor and uses the same Sheaffer Skrip Slim ink cartridges as with the Slim Targa. The cutout ‘S’ in the clip stands out from other Sheaffer models. The earliest known advertisements for this model range are from 1984 showing a brushed chrome ballpoint and pencil set. Fountain pens of this line don't appear until about 1991 and very few advertisements are found. Included instructions give no indication that these pens were sold with converters or how to use one with the pen. The stainless steel gold plated nib is stamped SHEAFFER over F-4 over M. Nibs were available in extra fine, fine, medium and broad points. The pen appears in the 1991 Sheaffer catalog for $32 along with matching rollerball and ballpoint pens and a matching pencil. Available finishes in 1991 were Stainless Steel, Gloss Black, Gloss Burgundy, Gloss Blue, Gloss Grey, Matte Black, Matte Burgundy, Matte Blue and Matte Grey. The Stainless Steel models were slightly less expensive, with the fountain pen retailing for $25. The line was phased out probably by 1994 with the introduction of the new USA made Sentinel ballpoint and pencil. #fountainpen #pencollecting #sheaffer #sheafferpen #targa #slimtarga #sheaffertarga #penhero https://www.instagram.com/p/CCWveOgjNv-/?igshid=9jjsw527qq8c