diff --git a/EXeExecutor.h b/EXeExecutor.h
index 7136f59..eae8015 100644
--- a/EXeExecutor.h
+++ b/EXeExecutor.h
@@ -471,6 +471,7 @@ EXE_EXPORT bool ExeSurfFrAdd( int nId1, int nId2) ;
 EXE_EXPORT bool ExeSurfFrSubtract( int nId1, int nId2) ;
 EXE_EXPORT bool ExeSurfFrIntersect( int nId1, int nId2) ;
 EXE_EXPORT bool ExeSurfFrOffset( int nId, double dDist, int nType) ;
+EXE_EXPORT bool ExeSurfFrTestExternal( int nId1, int nId2, double dMinDist) ;
 EXE_EXPORT int  ExeExtractSurfFrChunkLoops( int nId, int nChunk, int nDestGrpId, int* pnCount) ;
 EXE_EXPORT bool ExeSurfFrMoveSimpleNoCollision( int nId1, int nId2, const Vector3d& vtDir, double& dLen, int nRefType) ;
 EXE_EXPORT bool ExeSurfFrRotateSimpleNoCollision( int nId1, int nId2, const Point3d& ptCen, double& dAngDeg, int nRefType) ;