Check the listing for details. Xentric Guitars - HALLOWEEN Series Resin Shaped Knobs. Condition: New. Listed at 12.95 USD. XENTRIC GUITARS™ HALLOWEEN Series Shaped Resin 6mm Knobs★Made From Urethane Resin (Not metal)★★Knob Color May Vary Slightly From Picture★Knob Information:Simple and Easy to InstallIntricate Detail, Painted By HandMade of Extremely Durable and Lightweight Urethane Resin Which Allows for Vivid Colors ★★★These knobs are not made of metal★★★Every Knob Includes an 8-32 set screw to secure the knob to the shaft.Instructions:Back out Set Screw Slightly to Allow Easy Placement Slide Knob on Shaft to Desired Height Align Set Screw with Split in Shaft. (Split Shaft Only.) Failure to properly align can result in knobs coming loose, falling off, and being lost. Tighten the Set Screw. Do not over tighten to avoid stripped threads or damage to knobs/shafts.★HALLOWEEN Series Knobs Come With BLACK Set Screws. Please let us know if you would like a different option★Returns:Please note we WILL NOT accept returns from any buyers who did not read the full product description and are expecting our knobs to be made of metal. *See first line in product description above.