How an electric shock insect killer working?

There are two main types of electric fly killers. The traditional electric zapper(or shock) and glue board stick type killer. Each works in a different way and has its own benefits:
Fly Zapper
A fly zapper has two main components – fluorescent ultra-voilet(UV) tube bulbs and an electrified metal grid. As most flying insects are attracted to bright ultra-violet light, the bulb helps to entice the pests onto the electrified grid, which then vaporises them on contact.
Effective: kills in an instant.
Mess-free: dead insect body drops into an easy-clean collection tray.
Low maintenance: aside from the occasional bulb change and cleaning, electric fly zappers take very little maintenance.

Good to know: particularly large or stubborn insects may take more than one zap to kill. In addition, not all insects are attracted to ultra-violet light. Just like humans, some flies can be colour blind too!

Glue Board
Glue boards are sometimes called glue traps or just fly traps. Working in a similar way to a zapper, the glue board uses a fluorescent ultra-violet light to attract insects, which are then trapped against replaceable sticky boards.

Quiet: aside from the noise of a fluorescent bulb, glue boards are otherwise silent. No tell-tale zapping noises when a fly is caught.
Discreet: as there’s no need for an electrified grid, glue boards are usually smaller than zappers.
Clean: glue boards are really easy to keep clean - you simply change out the board when required.
Good to know: once a fly is caught, it will stay there until you replace the board. For hygiene, it’s important to change the boards regularly. During hot summer months, this may need to be done weekly.

For a summer,a pest killer lamp divide into two type,one is high voltage electric shock type,another is glue stick type,both need to use UV or LED tube to attract the fly or mostuito or other pest,and kill them with grid or board,mostly use for restaurent or food processing shop,help to reduce the quantity of the pest.