It's a most popular products in recent market. Our clients sell very well in Europe market, but there are still some country don't sell this products. we want to promote this products to some countries which sell little this products or even don't know this products. For this products, there are many advantages, when you buy one sets for printer, you will never need change the ink cartridge, you can use untill the printer damage. Each time, when the ink run out, you can refill the ink with the bottle directly in the outside of printer, it's very convenient. Also the unit price is more expensive than ink cartridge.but it's worth.