U.S. remanufactured Pitney Bowes SL-870-1 fluorescent red ink cartridges are the highest quality replacement cartridges on the market. Using only original Pitney Bowes SL-870-1 fluorescent red cartridges, we remanufacture each cartridge to the highest quality standards to match OEM ink level, color, and performance guaranteed! USPS approved. Our remanufactured postal meter red ink cartridges all exceed USPS® requirements for fluorescence.