If you purchase your InEarz Audio custom in-ear monitors directly from us, you may upgrade them within two years of manufacture to any equivalent or higher InEarz Audio custom in-ear monitors with ADEL, and we will apply 50% of the original price towards your new InEarz custom in-ear monitors purchase with the ADEL option. The original set of InEarz custom in-ear monitors must be returned in good working condition, and become the property of InEarz Audio upon completion of the Residual Upgrade process. The Residual Upgrade Guarantee only applies to custom in-ear monitors and may not be combined with any other coupon or discount. Universal-Fit in-ear monitors are excluded.