Each tube contains 10 charcoal discs.
 
Care must be taken when using these as they do become very hot. Place within a cast iron cauldron, soapstone incense burner or an abalone shell (with salt or sand) always ensure the holder is placed onto a hard surface - ideally slate, marble etc rather than wood or a cloth covered surface as it can get hot.
 
Light the discs using tongs to hold and light from underneath and when the charcoal disc is glowing and disc is starting to turn white, the resin/herbs are placed on top to emit a wonderful scent.