This CMC (Carboxyl Methyl Cellulose) or Tylose powder by Cake Craft is a man-made gum used as a flower glue or a hardening agent which when added to fondant, creates a quick version of gumpaste/modelling paste. Comes in a bulk 1kg tub. Also available in 100g bottles.

Instructions
Add a small amount of Tylose to fondant until it feels pliable, like modelling clay, to help harden it when modelling.

Handy Tips
Mix Tylose Powder to fondant only when you are going to use it.
Leave decorations overnight to let them completely set.

Ticalose CMC 2500 Fine Powder is manufactured and packaged by Tic Gums in bulk 50 pound bags. 

Carboxymethylcellulose is commonly referred to as CMC or Cellulose Gum. CMC Fine Powder is a bakery ingredient compatible with a wide range of products including proteins, sugars, and other hydrocolloids. The material controls texture and ice crystal growth in frozen dairy products. Ticalose CMC 2500 is ideal for bakery products because it retains moisture. It can also be used for low-calorie formulas. Other uses for the powder are syrup, dairy, instant beverages, snacks, sports powder and nutritional sport products. It thickens sugar-free table syrups.