No balls in this baby, choose a solid metal core made of Stainless Steel or Titanium.  Simple, straight forward, low maintenance and at unbeatable price.  This kit includes everything you need but a bubbler.  

Includes:

• Crossing Technology PID
• 20mm Coil with Handle
• Thermal Twist Injector Core (Choose 316 Stainless Steel or GR2 Titanium)
• Coil Heat Guard
• Glass Bowl with Passthrough and 14mm Female to 19mm Male Adapter
• Coil Heat Stand
• Herb Scoop
• Wood Brush