These beautiful burners are Plug In (UK plug.) wax sold separately!! 
 
Small dish so doesn't require many melts but fragrances will certainly pack a punch 😜☺️
Bulb- 15w small screw in Bulb Can be replaced by carefully and very slightly pushing in and twisting the plug then simply screw out the bulb. 
To put back in again slightly push the plug and twist
 
**CAUTION** Burner gets VERY HOT so keep out of reach of children and pets! Once switched off the burner cools quite quickly and can be cleaned with kitchen roll or another form of wipe.