Instruct: Classify an Amazon review into positive or negative sentiment.
Query: A quality piece of equipment

A check of online comparisons had given the First Alert SA302CN battery-powered smoke and fire alarm high marks, and so far I haven't been disappointed.The unit is of very sturdy construction (especially the cover hinge and latch) and was easy to install, and inserting the battery involved none of the often-encountered hassles of trying to properly line up the terminals in a flimsy bracket tucked behind the sensor unit--a twist of the wrist rotates the unit off its mounting plate, and the battery slips into a carrier that then flips into place to make the proper connection, which is confirmed by a short 'beep' signal. Once the unit is back on its base plate, the red light indicating that the unit is operating properly is easily visible.This is easily the best smoke detector that I have ever purchased.