This Summit pen turned up in nearly unused condition – when I flushed it there was ink in the feed but it showed no other signs of having been used. It’s a little unusual in that there is no barrel imprint, so I can’t say what model it is. Everything about it suggests that it is a late model, perhaps among the last range that Summit made before the company closed in 1955. The “over the top” clip is a late feature.
The machined pattern is very crisp and the chrome plating is immaculate. The box, too, is in very good shape, though there is a little scribbling on the top.
I suppose one might say that this is a fairly basic pen but it’s interesting in that it appears to be quite an uncommon model. It is also unusual to find one in such good condition.
Goodwriterspens's Blog 
Deb,
Happy to be helpful. I have the identical pen, with sticker, and full imprints on nib, barrel and clip, but in “bottle green” color. It is, indeed, a late model from the 50’s. I had several lengthy e-mail discussions with the seller from England who runs the Summit site online. It is an S.160, made in Liverpool by Curzon’s.
Stuart (across the pond)
That’s interesting, Stuart. They changed the name from Curzons to Summit after the war. Regardless of which name is used they are all Langs pens.
Deb,
I neglected to say that my pen, also a lever-fill, is trimmed in what appears to be gold plate and has a F to B semi-flex nib. It was also made in button-fill and designated as S.165. A photo of one such pen appears on the Summit site at the moment.
Stuart (across the pond in the colonies)
That sounds a bit more upmarket than my one.