Sentry Ultra Pro Earbuds Review | USA 2021 This Sentry Ultra Pro review aims to compare Sentry’s top-of-the-line earbud headphones against some of the top-of-the-range noise-cancelling models from Sennheiser, Philips and other well-known manufacturers. A Sentry pro series can cost up to three times as much as a similar model from a competing brand, so […]