The plainest Sentinel and, for a lot of people, the best of them: brushed chrome from end to end, with chrome trim and nothing else going on. No lacquer to chip, no colour to date, just a satin metal finish that hides fingerprints and wear better than any painted barrel will.
The body is metal throughout, slim enough to sit comfortably in a shirt pocket, and works on a straightforward click-top mechanism. It takes the Sheaffer K-style ballpoint refill.
Sentinel dates back to the 1940s at Sheaffer, when the name marked out White Dot pens with a stainless steel cap - so an all-metal finish is arguably the most honest version of it.