All MSE cartridges are individually tested during manufacturing and must pass through a Triple Quality Control inspection before they get shipped to you. Our stringent quality standards include testing each component prior to manufacturing, during production, and even after our products are on the shelf.  We even subject our products to extreme conditions such as temperature, atmospheric pressure, humidity, and simulated shipping conditions to ensure the product performs perfectly in every situation, every time. The result is a high performance product that produces darker prints and sharper graphics.