First falls on the detector a pretty appealing design features.
In numerous tests, the ST-620 consistently receives positive reviews.
Another striking feature is the simple assembly (2 screws) and the ease of use.
Both the off and the test is performed by briefly pressing the large white button in the center of the detector.
In my currently does not have any signs of battery weakness, but also runs less than six months.
If, however, once the battery go broke, this is not readily replaceable. According to other reviews, the manufacturer is not accommodating in this case, and the devices often migrate into the garbage.
In this case, change the batteries turned out to be not so difficult - unless you can solder.
First, the housing is opened using a screwdriver (around is clipped)
Then one has the upper part and lower part of the chassis adjacent to each other and see the battery with the two soldered cables. There is a CR 17335 battery with 3 volts, this is not particularly expensive (about 7) and also available here on Amazon.
Now just have the old battery is removed and the new are soldered (note the polarity!) And has first again rest. Assemble by adding more clips of the housing halves.
