The Nitecore EMR30 Rechargeable Mosquito Repeller and Power Bank creates a comfort zone free of pests with a radius of up to 20'. Ideal for family picnics, barbecues, and holidays, the EMR30 accepts up to two blue pyrethroid-based pads that are activated by electronic heating. This means no more messy or expensive refills and no fire hazards. You can double the pest repelling potency by also activating the 25 to 40 kHz ultrasound function to drive away annoying bugs. A USB-C port allows for easy recharging, while the built-in power bank functionality lets you charge your smartphone or other devices.