If you are looking for a separate numpad for number crunching at work, and want it to look less boring the new KiiBOOM Phantom 21 is a numpad that you can consider. The KiiBOOM Phantom 21 retails for US$89.
Build quality and design
Consistent with KiiBOOM’s Phantom series of keyboard, the KiiBOOM Phantom 21 has a transparent aesthetic that lets you see the internals of the numpad. If you already own the Phantom 81 V2, you are able to achieve a consistent look even when getting a separate numpad. The KiiBOOM Phantom 21 comes in four colour options – (1) purple, (2) pink, (3) blue, and (4) clear, (5) black. I have both clear and black units. The back weights and keycaps are all colour matched accordingly which is a nice attention to detail.
Build quality of the KiiBOOM Phantom 21 is consistent with my experience of the Phantom 81 V2. It feels very solid and sturdy despite its main material of acrylic. There is a decent heft and weight to the numpad as well, which makes it feel premium. The quality of acrylic used feels high quality as well. The acrylic used on both top and bottom cases are thick with nice curved edges. This detail in the construction makes the keyboard feels premium and well built, even though it’s made of acrylic.
On the back of the KiiBOOM Phantom 21, you’ll find the USB-C port which is right aligned. It is located next to two switches, one to toggle between the three modes of connectivity, and the other to switch between macOS or Windows. There is even recessed area to store the 2.4GHz USB dongle when not in use.
The KiiBOOM Phantom 21 uses the same kind of SA profile transparent keycaps as the Phantom 81 V2. It is colour matched as well so the Black variant will get smoked black keycaps instead of clear ones. This will have some effect on how the RGB lighting will look like as it passes through these keycaps.
Typing acoustics & experience
The KiiBOOM Phantom 21 uses the same “silicon sandwich” gasket implementation on the Phantom 81 V2. The PCB and plate assembly is wrapped by the silicon layer which have tabs that act like gaskets. Given the small size of the keyboard, the Phantom 21 does not have too perceivable flex, unless you go looking for it by pressing down hard on it. It is not a stiff typing experience so that is good.
As for acoustics, the sound is very similar the Phantom 81 V2 – marbly clack sound signature that is more pronounced towards the lower frequencies. The KiiBOOM Phantom 21 is hot-swappable if you wish to swap out the KiiBOOM Crystal linear switches.
There is also a knob located at the top left of the KiiBOOM Phantom 21. By default, it controls the volume of your device. You can change the behaviour of it via the KiiBOOM software (which will be discussed below).
Connectivity, battery, and support
KiiBOOM Phantom 21 has tri-mode connectivity so you can use it (1) wired, (2) via Bluetooth, or via 2.4GHz wireless connection. The Phantom 21 has an 1,900 mAh battery but KiiBOOM did not indicate how long it will last. I have been using it for about 2 weeks since I received this, and it hasn’t shown any indication of low battery.
The software that allows customisations and remapping on the Phantom 21 is unfortunately not VIA. Instead, you’d have to download KiiBOOM proprietary software to gain access to these features. The software UI is a little clunky but it still works.
Conclusion
The KiiBOOM Phantom 21 is an attractive option for anyone looking for a uniquely designed numpad or if you simply want to have a consistently look from other Phantom-series keyboard that you own. Its quality build and tri-mode connectivity commands a US$89, but the lack of VIA support may put off some users.