Kokuyo PS body knocks

I’m looking for information on the Kokuyo PS-x series of body knocks.

I have in my collection:
PS-1, 2, 3, 4 and 11.

I’m aware of some triple digits in the series PS-102, etc.

What other models are there in this line?
Were these sold worldwide or only in Japan?
Edit: are these all considered part of the Mistral series?

I’m out of town, or I’d post a photo of them.



There were quite a few PS numbers of the KOKUYO Mistral series. In some cases, I’ve seen model numbers reused for several style variants, like the PS-3 (black stripe steel, then solid blue).

I’ve not yet found anyone who has created a full gallery of all KOKUYO Mistral variants. That would be terrific to see.

As for 2 digits, I know for certain that there’s a PS-12 and a PS-13.

As for 3 digits, there are 3: PS-100 (satin finish stainless steel), PS-101 (black), and PS-102 (gold).

From what I’ve experienced, there are some slight mechanism differences across the line. The lower end works fine, but compared to higher models it feels like it lacks refinement. Going from the PS-1 to the PS-12, I sense a difference. And then from PS-12 to PS-100? Even more pronounced. The 3 digit line has very smooth action.


Top 2 have what I call a “space tip” (streamlined, aerodynamic, looks like the front of a space shuttle), and unfortunately, I don’t have any of these specimens.

Based on looks alone, though, I’d guess those are significantly better feeling to write with than the other models (which I thoroughly enjoy).

I guess what I’m saying is I kinda think the lower models are child’s play compared to the more substantial and streamlined designs at the top.

PS: My collection is a f----- joke for not having the top Mistrals :unamused:


Nah, body-knock is not for everyone. There’s a certain lack of “elegance” with the body kinking at the half-way point. Like a plumber bending over and showing his crack for just a sec while he picks up his pipe wrench. :smirk::smile:

You have a terrific collection, and with how much you’ve laid out for it, rightly so.

Some consider the all-gold body rather gaudy, but having it in hand… it’s like a large golden bullet. I like it. I’m still trying to pick up a black one. An auction just closed from that seller we know plays games. And in his example there were some visible scratches… so I didn’t bid high and got beat out. One of these days…

You know, with the single digit models, I’ve always thought of the nose cone as “space capsule” shaped with how it mates to the body. To me, the top ones are like ICBM super-missiles.


I think you misunderstood—I have plenty of Kokuyo Mistrals and am a big fan (all of which are body knocks). But they are all kinda lame compared to the spaceship-tipped top tier models.


If you want to find more, use these words: コクヨ ミストラル → kokuyo mistral; デスクペン → desk pen; ボディーノック → body knock

Most of models are listed in this picture, but it’s not over yet, so I’m going to add some more information:

PS-3-1 (stripe, but it’s not etched)


PS-11 (those in the middle) (their threads at the tip and rod joints are plastic, I heard that these are later models)

PS-12 (their threads at the tip and rod joints are plastic, I heard that these are later models)


And a relatively young series that was discontinued only in recent years

collaboration models with trystrams called: Orobianco


I was just joking – (presuming, no top tier as you didn’t see worth spending more on body-knock style). Do you have the PS-3, or PS-13? They’re actually pretty good. But no doubt, the PS-100/101/102 are the best looking and constructed.

In all seriousness, I think a well made body-knock is the best lead advancement mechanism. No complicated auto-feed. It’s the simplest hand gesture–a gentle squeeze by bringing the rear part of your thumb inward and “knock”–lead is advanced. No writing finger movement. No disruption of your grip or orientation of the pencil. It’s pretty much ideal.


Wow! Linus, you are the KOKUYO Mistral Meister of Knockology. :sunglasses: Seriously impressive collection.

A few questions:
Are there 2 black striped Mistral models? The ones I’ve seen have always been marked PS-3, and your photo is the first I’ve seen of a PS-3-1. It’s a shame the black lines are painted on, instead of etched.

How is the PS-4 mechanism, compared to the PS-3-1? I assume it’s the same, but the PS-4 is ¥1500 while the PS-3 is ¥1200. The body construction looks a little more premium on the PS-4.

Here’s another marked PS-4. But it’s black with gold accents. I wonder why KOYUKO reused this model number… unless this is a sticker application error.

I never really cared for the more recent Mistral models, which remind me too much of Cross Century pens/pencils. But those Orobianco collaborations look really amazing.


Kokuyo added corresponding ballpoint pen for most models in Mistral series, I heard it was at a later date. Their model number starts with PR-xxx, use similar body knock mechanism. In particular, for the desk pen, all black part of bp version is made of plastic while mp version is all made of metal.


Oh, no, these are all Internet pictures. As for my own collections? Actually I only have PS-1, and I’m not a huge fan of this collection, even though I do know there’re people who have completed the entire Mistral collection. My favorite body-knock type models include check pattern PS-4, PS-1, brush pattern PS-12, Artline and 2000 yen version Angle, it will be a long time before these collections are completed hhh.

I think there’s only one black stripe model which has the model number PS-3-1 printed on the side, and a PS-3 sticker on the front.

PS-1, PS-3 and PS-4 share the same body shape and structure. And those PS-10x also share same things among themselves.


Got it.

I see you mentioned the Artline. The Shachihata is such a great pencil, for the price. The telescoping feature is really handy. The mechanisms I’ve seen overall are a bit clunky, like some of the Mistral models (e.g. PS-1, PS-2), but they do smooth out a bit over time of use.

A number of years ago, you could pick up the Artline for ¥1000~¥3000 in used to mint boxed condition. These days they’re not appearing on YAJ very much. There’s also a matching ballpoint that’s also telescoping, where lengthening it automatically extends the tip. AFAIK, they were made in brushed steel and then various lacquered colors (black, blue, red).


Are there 2 hairline mistrals? Ps-12 is in the picture but I think there is one with single digit, too?


Here are several articles about Kokuyo PS pencils by the same author.


An unfortunate but understandable minus for the Desk Pen companion to the PS-20 Mistral Desk Pencil, is that the pen is NOT a body knock design. It is simply a long ballpoint with a permanently exposed tip that goes into a desk holder. Confirmed this recently with a post by Masato 2020… the desk pen sleeve does not say ‘Mistral’.


The author also reproduced a paper from the 1980s about the structure and mechanism of body knocks.


I really want the black printed line pattern one.

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I am not able to translate the article itself (seems to be pictures), but wth are they doing? :-o :wink:

The folding type (middle folding type) is an imaginative way to remove lead from mechanical pencils. It uses simple principles to achieve the minimum change of hand posture during the lead extraction operation. Due to its simple structure, the durability of this lead extraction method is no less than that of ordinary pen tail pressing. Therefore, the middle-folding lead extraction method has become the best lead extraction method in my opinion.

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Try OCR?

Yeah, in some way this will work. But, honestly, that’s more theoretical background on body-knocks than I ever wanted to know :wink: