diff --git a/code/material.config b/code/material.config
index a47ea938b..af61a21fd 100644
--- a/code/material.config
+++ b/code/material.config
@@ -85,6 +85,7 @@ gdot0_slip              0.001
 n_slip                  20
 tau0_slip                 31e6                # per family
 tausat_slip               63e6               # per family
+w0_slip                 2.25
 gdot0_twin              0.001
 n_twin                  20
 tau0_twin                 31e6               # per family