Almost every keycap is made of one of two plastics. Neither is the premium one. They feel different, wear differently and sound a little different, and good and bad sets exist in both.
| PBT | ABS | |
|---|---|---|
| Surface | Slightly textured, dry to the touch | Smooth |
| After a year of use | Stays matte much longer | The most-used keys turn shiny |
| Sound | Tends to be deeper | Tends to be higher and sharper |
| Colours | Softer, more muted | Brighter and crisper |
| Common legends | Dye-sub or double-shot | Double-shot |
PBT
PBT is the harder plastic. It keeps a fine texture that resists the polished look keys get from finger oils and wear, so a PBT set looks new for longer. Its weak spot is long keys: PBT shrinks more as it cools in the mould, and a spacebar can come out very slightly bowed. Good sets control for this.
ABS
ABS is smoother and takes colour better, which is why the brightest sets and the clearest see-through ones are ABS. It moulds very precisely, so legends are sharp. The trade is shine: the keys you press most will go glossy with use. Some people like that worn-in look. If you do not, pick PBT.
How the legends are made matters as much
- Double-shot: The legend is a second piece of plastic moulded through the cap. It cannot wear off.
- Dye-sub: The ink is sunk into the plastic with heat. It does not wear off either, and it works on PBT, usually as dark legends on a lighter cap.
- Shine-through: The legend is translucent so backlight comes through it. Needed if you want lit legends.
What changes the sound more
The plastic is only part of it. Thick caps sound deeper than thin ones in either material, and a tall profile such as SA sounds fuller than a low one such as Cherry. If sound is what you are shopping for, look at thickness and profile before the plastic.
Which to pick
Pick PBT if you want a set that stays matte and you like a dry, textured feel. Pick ABS if you want the brightest colours, a see-through set, or the smooth feel. Either way, check that the set fits your board: MX stems, and the right sizes for the bottom row and right Shift.
