Cobalt POM Review: POM Linear Switch That Thocks & Pops
May 3, 2021 Andrew Cheng

Aside from the NovelKeys Cream switch – which I personally quite like for its clacky sound profile – you don’t usually see switches in the custom mechanical scene with POM housings. This is precisely why JWK’s Cobalt POM linear switch is particularly interesting.

Not only does it have a POM housing, the Cobalt POM also features a stem made out of a “proprietary blend of plastics.” I’ve been using this switch on the KBD67 Lite for a while now, and I absolutely love its thocky, “poppy” sound profile and smooth downstroke.

Of course, the Cobalt POM still has its fair share of shortcomings. But overall, it’s easily one of my favourite switches right now, especially if I’m planning to build a keyboard with a deep sound profile.

What It Is

The Cobalt POM is a linear switch manufactured by JWK, and it’s quite similar to the Durock POM switch. Both feature the same POM housing with a five-pin design, a “mystery blend” stem, as well as a slow 63.5g spring. The Cobalt POM, however, is factory lubed, while the Durock POM is available dry or lubed.

As for availability, the Cobalt POM is sold on Prime Keyboards and iLumkb; I got this switch from the latter, given that the Singapore-based vendor is closer to where I am (Malaysia). Sold at S$9.50 on iLumkb for 10 switches, that puts this switch at around RM3 per unit, which is fair for a switch of this quality.

The Good Stuff

The moment I started typing on the Cobalt POM, its deep sound profile is immediately obvious. Not only does it have a solid, deep-sounding downstroke, the switch’s long stem pole also produces a “poppy” bottom out. The topping out sound, even if it’s a tad louder, is solid too.

Thanks to its lubed nature, the Cobalt POM offers a smooth downstroke as well; comparable to the C3 Tangerine V2, even. While there’s a hint of audible scratch, there’s absolutely no scratchy sensation throughout the downstroke. The consistency of the lube across the 90 switches I got seems to be quite good as well.

Another aspect of the Cobalt POM that’s worth highlighting is its long 63.5g gold-plated spring, which offers a slow force curve. Basically, the initial force at the top of the key press will feel heavier than, say, a regular 65g spring. Yes, even though this spring has a lower 63.5g bottom out, it will feel heavier because it is a slow spring.

Last but definitely not least is the colourway of the Cobalt POM. The combination of the dark blue stem and grey housing give it a unique-looking design that sets it apart from other switches in the market now. I personally quite like how it looks, though I’m sure there are folks who don’t share my sentiment.

Nonetheless, at least the Cobalt POM doesn’t look boring at all.

The Bad Stuff

Though the Cobalt POM has quite a number of positives, it certainly has room for improvement. The spring, for one, pings quite a bit. Even though the factory lubing is quite consistent, only the stem is lubed; other parts of the switch are bone dry as far as I can tell.

Of course, the solution to this spring ping issue is simple: just lube the spring. While the Cobalt POM feels smooth out of the box, a proper lube job will definitely make the switch even smoother while also removing the spring ping. Trust me, it’s (almost) always worth lubing switches for a more pleasant typing experience.

Aside from that, the Cobalt POM’s PCB-mount legs are thicker than regular MX-style switches too. This, in turn, makes it quite difficult to mount them onto my KBD67 Lite. Depending on which keyboard you plan to use this switch on, you may need to thin the legs with a pair of pliers.

Is It Worth It?

If you want a linear switch that is quite smooth out of the box with a deep, thocky sound profile – as well as a slow spring – the Cobalt POM is a great choice. But to really bring out its full potential, you really have to lube the switch to eliminate the spring ping and make it even smoother.

While it’s unfortunate that the Cobalt POM’s legs are thicker than usual, it’s not a problem that cannot be solved with a little bit of DIY. If you’re willing to do that, and lube the switch accordingly, you will be very, very happy with this thocky linear switch.