The Stihl Bump Head Knob 4006 710 4001 is a genuine replacement part designed for Stihl string trimmers. Made of durable black plastic, this contemporary-style spool cap ensures high-quality performance and longevity for your outdoor power equipment. Perfect for maintaining your yard and garden, this Stihl-specific knob is a reliable and essential component for keeping your grass looking neat and well-manicured.