Viscous 35% phosphoric acid gel ideal for total etching. It penetrates the finest fissures and does not run on vertical surfaces. It features a unique self-limiting etching depth. The gel is a deep blue color for good visibility. It rinses off easily without leaving residues. IndiSpense System: a convenient and economical filling system. Allows for refilling empty 12 ml syringes from a 30 ml IndiSpense syringe.