diff --git a/EGkVolZmap.h b/EGkVolZmap.h
index 433b706..361e2cf 100644
--- a/EGkVolZmap.h
+++ b/EGkVolZmap.h
@@ -73,6 +73,7 @@ class __declspec( novtable) IVolZmap : public IGeoObj
       virtual bool SetGenTool( const std::string& sToolName, const ICurveComposite* pToolOutline, int nFlag) = 0 ;
       virtual bool SetMortiserTool( const std::string& sToolName, double dH, double dW, double dTh, double dRc, int nFlag) = 0 ;
       virtual bool SetChiselTool( const std::string& sToolName, double dH, double dW, double dTh, int nFlag) = 0 ;
+      virtual bool SetAdditiveTool( const std::string& sToolName, double dH, double dR, double dRC, int nFlag) = 0 ;
       virtual bool SetCurrTool( int nCurrTool) = 0 ;
       virtual int GetToolCount( void) const = 0 ;
       virtual int GetCurrTool( void) const = 0 ;