3. Some may argue that smoke detectors shouldn’t necessarily have an elegant exterior and that functionality is more important than the design. While it is true that a smoke detector should have its main focus on the reliability factor, it is also a device that will undoubtedly attract some attention since it will be either mounted on the wall or ceiling. So, aesthetics are important and it is nice to see that the newer smart detectors are better looking with each iteration and have taken advantage of different types of LEDs. But, sometimes, a flashy design is overkill and a simple, non intrusive case is the better choice some don’t like a multitude of LEDs to shine from their ceiling. As you may have guessed, the First Alert SCO501CN 3ST indeed features a relatively simple white round case, on the front with a large Test/Silence Weekly button, as well as two LED indicators CO and Smoke and several cut out areas in form of a leaf and underneath it, there’s the speaker. On the lateral side, you’ll be able to identify a small cover which, when removed, will reveal a dedicated space for inserting the two batteries. The device is available as a battery only model and, unlike the PRC710 which has a sealed battery, the First Alert SCO501CN 3ST allows you to change the batteries as soon as necessary it requires 2 AA batteries – the negative aspect is that unlike the sealed batteries which can go up to 10 years which is usually the life expectancy of the smoke alarm, the removable type of batteries will last a lot less. The case of the SCO501CN 3ST is a bit more slimmer than the usual bulky smoke detectors, while maintaining an average diameter it measures 5. 0 x 5. 0 x 2.