transparent color----you can see ink level very clearly, big cartridge ----hold much more ink, 220ml each, neednot refill time to time.PP material body----top grade material to make it strong enough avoiding broken under high pressure. simple refill hole----refill ink is simple, just pour into ,easy work. Use for：EPSON COLOR3000/PRO7000/PRO7500，ROLAND 500/600，MIMAKI JV4，MUTOH RJ8000 etc