Introduction

Cooler Master first showed off their low-profile mechanical keyboards under the SK600 series at CES this year, with the SK650 and SK630 coming out soon after. Our own review of the SK630 lays a strong foundation and then some for this review, if it interests you, given how much common ground is shared. Even then, a lot of attention was given to the Bluetooth hybrid members of the series, which was showcased in part by the 60% form factor SK621 that offered both Bluetooth 4.0 and USB connectivity while still retaining the same feature set as the wired versions of the keyboard series. Cooler Master had plans at the time, and they may still, to bring out SK651 and SK631 wireless variants of the SK650 and SK630, but portability is the name of the game when it comes to this, and we thank Cooler Master for sending along a sample of the SK621 for review.


The SK650 is a full-size keyboard (think 104/105-keys), and the SK630 is a TKL form factor keyboard. The naming scheme thus suggests that the SK621 would employ an even smaller form factor, which is exactly what we get. The use of the 60% form factor by a mainstream brand is quite interesting given the vast majority of the mainstream market for mechanical keyboards will just look and scoff at what seems to be a toy keyboard to many. Dig deeper, however, and it falls right in line with everything Cooler Master has done over the years in offering products to attract as wide a market as possible. In this case, the SK621 aims to attract keyboard enthusiasts, similar to what they did with the Novatouch TKL and MasterKeys PBT keyboards before. As with the SK630, the SK621 also aims to grab the eyes of the average Apple user who is used to low-profile, wireless keyboards, although without a mechanical switch option. We will go over the keyboard in detail in this review and begin with a look at the specifications below.

Specifications