Diamine 150th Anniversary 40ml Regency BlueDiamine has been providing widest color of ink refill in the world. Thorough out all the transition over the years, Diamine Co. has successfully maintained their status by providing excellent quality fountain pen refill with traditional process and techniques. Diamine ink is compatible with all kinds of brands. To rejoice the 150 years of grandeur, Diamine has introduces Anniversary Special Fountain Pen Ink Bottles in 8 different unique colors. Diamine Ink has been the foremost choice for the pen enthusiast.