You have to be careful ! . The original Sierra twist design by BereaHardwoods quickly became very popular, and it has been imitated by many companies.
These "copies" may look almost the same on the outside and mostly use a 27/64" diameter tube close to 2.2" long, but the inside details are often a little bit different (and not interchangeable) and how they operate can be different as Chris (above) pointed out. . Some operate by twisting the barrel (Sierra) and some operate by twisting the top end finial.
I made a blanket statement a couple of weeks ago which was wrong when comparing the Sierra and a look-alike and I was pleased to get corrected here.
The people who know the Sierra "look-alikes" the best, and sell the biggest variety, are the ExoticBlanks couple, PR_Princess and ed4copies ( Dawn and Ed ). . I don't think they sell the Manhattan, or Sienna, but they do sell the Sierra, Ambassador, Diplomat, Gatsby, Zodiac, Ellipse, the Thank-you pen kit, a range of Le Roi kits, ... to name most of them, although I may have missed a couple.
It's worth noting that there is another common Sierra look-alike, called the Mesa which is sold by Woodturningz. . Don't confuse it with the Southwest Mesa originated by PSI.
To make for more confusion, there are yet more variants manufactured/sold by Oriental companies and European companies. . Sometimes the manufacturer and the retail vendor even use different names for the same kit !
And then we have the Sierra Click, the Elegant Sierra, the Sierra Elegant Beauty, the Lucida, the Aero, the Arrow, ... and more ! . I almost forgot to mention the Wall St !
And so, DB in VT, is everything clearer now ?! :biggrin: . Yup, there are different names, but there may be other differences also.
Perhaps I should point out that the Princeton mentioned above could be regarded as a variant of the Sierra because it uses the same 27/64" tube but it has a noticeably different shape ... which is identical to the Virage !
And how about the Pensar, which uses not one, but two, 27/64" tubes, each about half of the Sierra tube's length and joined by a coupling ring in the middle ... is it, too, basically a Sierra ?
I don't think this dissertation is anywhere near being exhaustively complete !!
Oh, just thought of another one ... the Monarch.
And ... the Napoleon, which is called something else by the manufacturer, Dayacom. . It is sold in Canada, but I think not in the US, although Smitty's Pen Works used to sell an extremely close kit which, I believe, was called the Le Roi Elegant Major. I don't believe that ExoticBlanks, who acquired Smitty's business, is continuing to sell this kit. . It uses the exact same tube as the Sierra twist but is more "high-end" having a crystal on the clip (like the Majestic Squire from PSI) and "advanced" platings (Rhodium, Titanium Gold, and Black Titanium). It is, in fact, one of my favorite kits.
Someday, somebody should catalog all these Sierra look-alikes comparing their similarities and differences.
Wanna get your Ph.D. in pen kit identification ? :biggrin::biggrin: