I first learned about the KOH-I-NOOR 5617 0.5mm when I first started deep diving into the history of the company and how its groundbreaking Rapidomatic series of drafting pencils became inextricably tied to the lore of the rOtring 500 and 600 families.
To keep it brief, the original Czech based company was nationalized in 1945 after WWII and became a separate entity from its USA-based operations. It was KOH-I-NOOR USA that carried on the development of drafting related tools and eventually partnered with rOtring to manufacture its Tintenkuli technical pens under the RAPIDOMATIC brand. In Europe, KIN would focus more on artist’s materials.
My speculation is that after the success of the RAPIDOMATIC / rOtring 500, KIN Europe could have licensed a derivative design from the OEM factory - resulting in the 5617 0.5mm. The nose-mounted lead degree window is a highlight, and I think I can spot an auction thumbnail at arms length by now.
As the 5617 is such a rarity, similar designs by other brands become interesting ‘substitutes’ when they cross my path. The first was the PYRAMID PP10x series, which I believe is a subsidiary brand of prolific OEM Kotobuki. I jumped through many language and payment hoops to order a handful direct from a Thailand e-store. I traded or gave away the 0.5 and 0.7 versions over the years, holding on to the 0.3.
Then, early this year, I spotted a post on X announcing a new series of original products by Kitera Shouji, which I believe is an office products company. They had previously came up on my radar when they licensed an exclusive ‘military green’ Smash from Pentel in 2022.
The KS-01 comes in black and blue colors, and seem to have evolved somewhat from the PYRAMID and KIN. For one thing, gone was the knurled metal grip. In its place was a simpler concentric grooved section in plastic, with a new chromed metal ‘collar’ just above the signature lead degree window.
In addition, the KS-01 also adds a slide-pipe function, along with spring cushioning for the clutch. For anyone looking for a 5617 stand-in, this is not too shabby.
Lastly, I couldn’t help but notice the KS-01 also bears some resemblance to another KOTOBUKI offspring: the Penac Protti PRC 103/105. Similar grip design, as well as sliding tip and cushioned feed.
