Keycaps made from this type of plastic tend to be matte and thicker than ABS plastic. The more expensive it is, the nicer texture can be.
In general, we can see that this type of keyboards are more expensive than ABS. This is because the production process for Polybutylene Terephthalate is much more difficult. It’s not easy for the material to form a proper keycap with the molds. And, the material is expensive itself. Of course, you can find some pricy ABS keycaps due to their unique designs.
You also can see the point from their name. This plastic is more durable and brittle than ABS plastic. Therefore, if you choose PBT vs ABS keycaps, you might not need to buy a new keyboard for a while.
Normally, this material is thicker than ABS. However, it’s not always true. You also can get high-end ABS keycaps and they will be thicker than cheap PBT keyboards. Moreover, you also tell the difference of the sound from PBT vs ABS keycaps. Since PBT are thicker than ABS, the sound when typing with Polybutylene Terephthalate is always louder than ABS keycaps. Moreover, the keycaps don’t vibrate too much when using.