Lead Regulator MPs 1983–2022

A couple of years ago I took a group shot of my MPs with an official lead regulator function, i.e. the function of controlling how much lead was dispensed per click was a documented function that was operated by an obvious external dial or knob.

I felt I had to say ’official’ because it has emerged that a certain vintage COLLEEN pencil has a similar capability but the adjustment is performed inside the body. That is to say, it is not obvious and may not have been intended by the maker. If this was documented by COLLEEN in the box or instructions, I’d accept it into this rarefied pantheon.

Anyway… at the end of 2022, OHTO released the MS01 series as a revival of sorts of the Super Promecha that was retired in 2020. And so a refresh of the line up was needed. L-R:

Tombow Variable SH-1500 VP (1983-1988). The oldest documented type (that I know of) with this function; produced in 0.3, 0.4 and 0.5mm.

Staedtler 925 95 (1999–2005). The second brand to offer this function, and I tend to think OHTO probably did this as an OEM, due to the Japanese sticker. Came in 0.3, 0.5, 0.7 and 0.9mm.

OHTO Super Promecha PM-1000S & PM-1500S (2003–2008). OHTO seems to like to keep things complicated, including their product line-up. This older ‘S’ series is split into 1000-yen and 1500-yen versions, the difference being the ‘upgrade’ of a hex barrel, removable clip and all-metal button.

Staedtler 925 85 REG (2004–2014). This is what most collectors would be familiar with aside from OHTO when they start searching for regulator pencils. The stand out feature is the unique cogwheel design of the button’s end cap. The tapered cone is also unlike the tubular style of most drafting pencils. I would say the 85 is closer in spirit to Staedtler’s style than the 95.

OHTO Super Promecha PM-1500P (2008–2020). Common sense seems to have arrived and OHTO kept it relatively simple, with the non-Super version kept at 1000-yen, leaving 1500-yen to the fully tricked-out Super version.

Further simplification in the ‘P’ version saw the deletion of the separate adjustment of tip length that came with the ‘S’ version. Some feel that this was a duplication of function since the rotating grip to retract the pipe could also ‘set’ the length. Some feel this is not as stable as the older design.

This version is also noted for its 4 embedded rubber ‘grip rings’, which can and do disintegrate, leaving behind sharp-feeling grooves.

OHTO Conception SP-1505C (2016). Still in production. This ‘contraption’ appears to be OHTO’s attempt to add a slide pipe gimmick in the wake of Pentel reviving the function with the Orenz. The design is typically OHTO… equal parts hi-tech and oddly weird.

OHTO MS01-SP3/5 (2022). Essentially a Super Promecha, but with slightly refined finishing and a deletion of the hated ‘grip rings’ from the PM-1500P.



What’s your favourite one and which one has the best regulator mechanism?

For me, the Tombow Variable and Staedtler 925 85 REG are the best by a wide margin. Curious to see what @drifand thinks…


I think all of the regulator designs have sweet spots and rough spots, especially when you push the setting to the extremes. So for pure feel of the adjustment, the Variable is tops for me. For visual feedback of your setting, the Conception is actually pretty useful.

The REG… I ding it for the bland homogenous colour theme… and don’t like to put it in rotation.

As for the setting, I try to find the sweet spot where the click feedback is ‘best’ and then dial it back to dispense a little less. I like having control by clicking more if I feel like it.


As a color scheme maximalist, I agree the styling of the 925 85 is disappointing. But the operation, grip, and comfort are top tier.


Nice post. Maybe you can add the Platinum Pro-Use to it. They have documented regulator function as well.


You’re making me dig out the Platinums just to see what I’ve missed! :smiley:


I tried searching on MSDA-2000 but didn’t turn up anything. I did come across MSDA-1500… which appears to have 2 controls. I know the first is for lead pipe extension/retraction, so I thought maybe the grip rotation is to affect lead length… but that appears to be cushioning control ON/OFF.


Msda 1500 is normal prouse 171, msda-2500 is the black one. Maybe x. meant that?


MY BAD! The Platinum is adjustable pipe length, not regulator!!!