SpectraTone Backbore Variations
We will stop taking orders for Kickstarter add-ons January 7th, 2022.
Your order must ship with your Kickstarter SpectraTone mouthpiece and you must include your backer number to be eligible for this promotion. Please choose "pick-up" option to complete checkout.
The Backbore is an extension of the Throat that determines tonal color, intonation, and projection pattern.
Beginning Diameter = .20 to .22 inches
End Diameter = .31 to .35 inches
* Extended length backbores are available to adjust gap and fit extra long receivers
A 3C backbore is typically .21 by .33 inches and is designated as 21.33.
Need help with sizes and options? Call us at 303.657.2747 or email email@example.com to discuss your needs with our team of experts. Over 60 standard sizes are in stock and ready to ship! Please allow up to 12 weeks for custom extended length and special sizes.