ThomasRyanHi @ThomasRyan , our earphones are made for those that desire the highest quality sound and build. These earphones feature the patented apex technology (air pressure exchange) which allows the trapped air in your sealed ear canal to vent while still keeping a full acoustic seal with a full range frequency response. With conventional vents you lose most bass, but not with apex. You can learn more about apex here: www.64audio.com/apex These earphones feature 4 proprietary balanced armature drivers and are tuned for very smooth highs, transparent mids, and punchy lows. Additionally they are hand-crafted in the USA with the finest materials feature a 1-year limited warranty on parts and labor.