This K&F Concept mini V-Mount battery has a capacity of 99Wh, making it airline-friendly. At 78mm wide by 109mm tall by57mm deep and weighing 643 grammes, it is pretty much the same as just about any 99Wh V-Mount block although this one has a metal sleeve around the front three quarters of the body in order to protect it from knocks. On the back, there is: the V-Mount itself - this one is plastic so I don't know how hard-wearing it will be; the BP connector block at the bottom; and, in the middle a light to see with, which is unusual although, potentially very useful in poorly lit situations.
On the front is a graphical display showing you the level of charge and when it is under load, it also lets you know the voltage and level of power going into any if the regulated sockets - that is to say that when using a direct connection such as the D-Tap, this does not show.
On the left hand side there is a push switch and with a short press, you see the display on the front but with a long press, you turn on the LED at the back - another long press turning it off. On the right hand side, covered with a water resistant flexible plastic cover, is the D-Tap connector which, on the review copy, was slightly misaligned at an angle, making it quite difficult to get the plug in there when compared to other blocks that I have, even though once it was in, it worked all right, supplying the the continuous 65 watts that I was drawing from it for a photographic light as you can see in the photograph.
On the top, again covered by a flexible plastic cover, is the main connection interface. In it are: a 12V DC connector (5.5x2.5mm); two USB C connectors - one labelled USB-C1 and the other labelled USB C2; and, a USB A socket. Of the two USB C sockets, the V-Mount blocks only seems to charge through USB C1.
Whilst the display shows you the voltage and the wattage for any active, regulated connection, unlike other V-Mount batteries, it does not give you an estimate of the amount of time left for the battery to run down. Also, although this in no way impacts on the performance of the battery, this is the slowest colour display I have ever seen, taking almost two seconds to replenish.
On the whole, this is a capable battery with plenty of connectivity and as all V-Mount batteries, it is very useful, whether you are running small studio lights from it, a camera rig or using it to charge your phone. The only thing it has against it is the poorly implemented D-Tap socket on it.