The Antec ISK300-150 is twice a large as the other Antec chassis, but still the second-smallest in the test. In the front it looks like you could install a full 5.25-inch drive, but that's not the case. Behind a cover there's a slot for a slim-line station. It does have two frontal USB 3.0 ports, eSATA and audio.
The integrated PSU provides 150 watts, enough for a decent system. There isn't a lot of space, only room for a single low-profile expansion card. It fits two 2.5-inch storage devices such as notebook disks or SSDs.
The cooling isn't very effective judging from our heat test. With fans on low the chassis goes up to 46.6 degrees. With fans on high that's reduced to 40.3 degrees, but then it becomes the loudest chassis in this test with 52.4 dB(A). There is room for an additional 8 cm fan, which probably improves cooling. We like this one more than the other Antec chassis.