Flexi Blue - R34WF Flexi Blue is the most flexible wax in the GRS Premium range. This wax has a high elasticity which gives the wax exceptional memory and durability. Flexi Blue is an extremely durable wax widely used for stone in place and will withstand rough handling and removal from very complex molds. Technical information Flow (cPs) Average elasticity (N) High Hardening point (61°C) Linear shrinkage (%) 1.7