An interesting pen for Sheaffer fans. Japanese pen giant Sailor made the Sentinel for Sheaffer in the 1980s.
The steel F-4 nib is a dead giveaway, and the sizing follows the Japanese. So while the nib has an “M” on it, it looks more like a Western F or XF.
When I first got it I didn’t notice the engraving on the cap: “AUPE BEST PERFORMANCE BR”.
What’s the AUPE? My guess is that it’s the Amalgamated Union of Public Employees. Ah, irony :p
writing without rhythm 
Hello, I have one of these in Matte Black. The nib is gold “F” with the heart cutout. It does not have a cartridge or converter. Do you have any idea what would fit? I was thinking of trying to find an old slim Shaeffer or would Sailor cartridges fit? Thank you so much in advance for any advice.
Hi! Mmm… my guess is that you need a slim Sheaffer cartridge or a button converter. A good substitute would be the Monteverde mini converter. I doubt Sailor cartridges would fit.
Sorry but I sold the pen a while ago so I can’t verify the cartridge size. Good luck!
Hi Jean, Can you use cartridges Sailor, I’ve tried it and go perfectly.
I have one I converted to an eyedropper filler by adding an o-ring at the joint between barrel and section, and giving the ring and threads a liberal coating of silicone grease. Then fill the whole barrel with ink and screw it together-not too tightly. Works well.
Credit for this idea goes to the guy who runs Noodler’s ink.
I’m surprised to hear this. I’ve heard one shouldn’t convert metal bodied pens to eyedroppers as the ink can corrode the metal. Have you seen any problems of this nature? The metal band on the front of the section of my own pen has been corroded over the years by ink leaking into the cap when left inked but unused for long periods.
Sailor cartridges can use, I’ve tried it and go perfectly.
I have one of these (bought new in the 1980s) and have used Pilot short international cartridges as those are easily obtainable here in South Africa. I’ve never tried but possibly the longer standard international cartridges would fit too.
Forgot to mention that mine has an F nib. Now I know it’s a Japanese nib it makes sense why this nib is so fine, close to or maybe even finer than the German EF nib on my TWSBI Diamond 530. But even though it’s so fine, it’s one of the smoothest writing pens I have.
Just bought a pack of those short international cartridges. My memory failed me, they are Pelikan brand (from Germany) not Pilot as I thought. I was going to see if I could get the longer standard ones to try in the pen but no luck. The fountain pen market here in South Africa is tiny the only cartridges to be found in the local stationers were Pelikan 4001 (the short international ones), Sheaffer Skrip, Wateran and Parker Quink.