AMERICAN MAILING SOLUTIONS INC. offers a high-quality, low-cost alternative to OEM postage supplies. Our products are manufactured in state-of-the-art facilities, and undergo rigorous quality assurance testing. These products are fully compatible with SendPro Mailstation (CSD1) postage meters. Our ink is specially formulated for the SendPro Mailstation (CSD1) postage meter. AMERICAN MAILING SOLUTIONS INC. uses our own products for service and supply to our customers. So be sure it is our brand when you purchase. Yields up to 400-880 impressions, the same as OEM. Offering more value than buying OEM. You can rely on our SL-870-1 cartridge to never prematurely dry up. Our SL-870-1 is USPS-approved, high-quality red fluorescent ink professionally formulated to work in your postage meter. We ensure consistently high print quality with every use. The 870-1 is a USPS-certified red postage ink cartridge with SendPro Mailstation (CSD1) compatibility. There is one (1) per box. Our ink is plug-and-play without any frustrating key prompts. Our SL-870-1 ink cartridge is readable if wet with no issues. The ink is widely used with envelopes, postcards, and self-mailers, either uncoated or gloss paper stock.