On sale at Aldi for $5.
The Aldi bug zapper operates off two AA batteries and activates with a button that you must hold in to power up. Surprising it works effectively. It cannot handle a swarm of larger bugs, and large bugs tend to take time to zap away. They get stuck and you have to tap the racket to clear them or they will prevent an effective "zap" for the next pest.
My wife went outside after dark to water some plants on the front porch and I went out with her. Just moving the zapper around her lower body, it killed a minimum of 10 mosquitoes in around 5 seconds.
It's a good feeling to get even for mosquitoes are real hard on my girl. I bought a second zapper for our PC.