Features Benefits:

• Replaces stripped spark plug threads in aluminum heads with 14mm spark plugs
• Installs a new solid steel spark plug thread insert in original thread location
• Set includes one-piece drill tap, long tap holder, short tap holder, insert installer, swedger and handle
• Includes four insert sizes: 5/16″, 7/16″, 11/16″ and 1″ (new size).