Korpa 
The o-port will make any guitar from beginner to custom-sound richer, fuller, and louder, with more clarity and better projection. the o-port material is custom blended for flexibility to prevent damage to your guitar finish and inlays. your o-port will suppress feedback and give your acoustic or acoustic electric guitar a fuller sound with more volume, better clarity and enhanced projection. available in two sizes:large nbsp; size - fits 3.875 inches - 4 inches (9.843 cm - 10.16 cm) small size ndash; fits 3.375 inches - 3.5 inches (8.573 cm - 8.89 cm)
- Gives an acoustic guitar a richer, fuller and louder tone
- Increases the projection, clarity and balance of your guitar
- Greatly aids in eliminating feedback. Available in small and large, black and ivory.
