diff --git a/src/tsqsim-lib/src/TSXformFactory.cpp b/src/tsqsim-lib/src/TSXformFactory.cpp
index 45b8e5e..80d7a5d 100644
--- a/src/tsqsim-lib/src/TSXformFactory.cpp
+++ b/src/tsqsim-lib/src/TSXformFactory.cpp
@@ -43,6 +43,8 @@ CorPtr<ITSXform> TSXformFactory::Create(const Str & name) const
             case TSXformType::SQRTS:    return CorPtr<ITSXform>(new TSXformSqrtSafe());
             case TSXformType::LOGS:     return CorPtr<ITSXform>(new TSXformLogSafe());
             case TSXformType::ADD:      return CorPtr<ITSXform>(new TSXformAdd(params));
+            case TSXformType::MUL:      return CorPtr<ITSXform>(new TSXformMul(params));
+            case TSXformType::DIV:      return CorPtr<ITSXform>(new TSXformDiv(params));
             case TSXformType::END:      return CorPtr<ITSXform>(new TSXformDiff()); // Fake
         }
     }
diff --git a/src/tsqsim-lib/src/TSXformImpl.cpp b/src/tsqsim-lib/src/TSXformImpl.cpp
index a328350..740bc6a 100644
--- a/src/tsqsim-lib/src/TSXformImpl.cpp
+++ b/src/tsqsim-lib/src/TSXformImpl.cpp
@@ -6,6 +6,7 @@
 #include <Math/GeneralMath.hpp>
 #include <Util/CoutBuf.hpp>
 #include <Util/CharManipulations.hpp>
+#include <Statistical/Assertions.hpp>
 
 using namespace EnjoLib;
 
@@ -117,7 +118,7 @@ TSXformAdd::TSXformAdd(const VecStr & params)
 }
 double TSXformAdd::Run(const TSFunBase & input, int idx, double valPrev) const
 {
-    return valPrev + m_add;
+    return Run(VecD(1, valPrev));
 }
 double TSXformAdd::Run(const EnjoLib::VecD & vals) const
 {
@@ -125,6 +126,41 @@ double TSXformAdd::Run(const EnjoLib::VecD & vals) const
 }
 double TSXformAdd::Invert(const EnjoLib::VecD & vals) const
 {
-    return vals.at(0);
+    return vals.at(0) - m_add;
 }
 
+TSXformMul::TSXformMul(const VecStr & params)
+: m_mul(CharManipulations().ToDouble(params.at(0)))
+{
+    Assertions::IsNonZero(m_mul, "TSXformMul::TSXformMul()");
+}
+double TSXformMul::Run(const TSFunBase & input, int idx, double valPrev) const
+{
+    return Run(VecD(1, valPrev));
+}
+double TSXformMul::Run(const EnjoLib::VecD & vals) const
+{
+    return vals.at(0) * m_mul;
+}
+double TSXformMul::Invert(const EnjoLib::VecD & vals) const
+{
+    return vals.at(0) / m_mul;
+}
+
+TSXformDiv::TSXformDiv(const VecStr & params)
+: m_div(CharManipulations().ToDouble(params.at(0)))
+{
+    Assertions::IsNonZero(m_div, "TSXformDiv::TSXformDiv()");
+}
+double TSXformDiv::Run(const TSFunBase & input, int idx, double valPrev) const
+{
+    return Run(VecD(1, valPrev));
+}
+double TSXformDiv::Run(const EnjoLib::VecD & vals) const
+{
+    return vals.at(0) / m_div;
+}
+double TSXformDiv::Invert(const EnjoLib::VecD & vals) const
+{
+    return vals.at(0) * m_div;
+}
diff --git a/src/tsqsim-lib/src/TSXformImpl.h b/src/tsqsim-lib/src/TSXformImpl.h
index 57338b8..306a739 100644
--- a/src/tsqsim-lib/src/TSXformImpl.h
+++ b/src/tsqsim-lib/src/TSXformImpl.h
@@ -45,4 +45,24 @@ struct TSXformAdd : public ITSXform
         double m_add = 0;
 };
 
+struct TSXformMul : public ITSXform
+{
+        TSXformMul(const VecStr & params);
+        double Run(const TSFunBase & input, int idx, double valPrev) const override;
+        double Run(const EnjoLib::VecD & vals) const override;
+        double Invert(const EnjoLib::VecD & vals) const override;
+
+        double m_mul = 0;
+};
+
+struct TSXformDiv : public ITSXform
+{
+        TSXformDiv(const VecStr & params);
+        double Run(const TSFunBase & input, int idx, double valPrev) const override;
+        double Run(const EnjoLib::VecD & vals) const override;
+        double Invert(const EnjoLib::VecD & vals) const override;
+
+        double m_div = 0;
+};
+
 #endif // TSXFORMIMPL_H
diff --git a/src/tsqsim-lib/src/TSXformType.h b/src/tsqsim-lib/src/TSXformType.h
index 0439ccb..fceb14b 100644
--- a/src/tsqsim-lib/src/TSXformType.h
+++ b/src/tsqsim-lib/src/TSXformType.h
@@ -10,6 +10,8 @@ enum class TSXformType
     LOGS,
     //POW, TODO
     ADD,
+    MUL,
+    DIV,
     END
 };
 
diff --git a/src/tsqsim-lib/src/TSXformTypeString.cpp b/src/tsqsim-lib/src/TSXformTypeString.cpp
index 10ad153..7d1db65 100644
--- a/src/tsqsim-lib/src/TSXformTypeString.cpp
+++ b/src/tsqsim-lib/src/TSXformTypeString.cpp
@@ -15,6 +15,8 @@ TSXformTypeString:: TSXformTypeString()
             case TSXformType::SQRTS:    Add(i, "sqrts"); break;
             case TSXformType::LOGS:     Add(i, "logs"); break;
             case TSXformType::ADD:      Add(i, "add"); break;
+            case TSXformType::MUL:      Add(i, "mul"); break;
+            case TSXformType::DIV:      Add(i, "div"); break;
             //case TSXformType::POW:      Add(i, "pow"); break;
             case TSXformType::END:      Add(i, "end"); break;
         }
diff --git a/tests/test-tsqsim/src/TSXformImplTest.cpp b/tests/test-tsqsim/src/TSXformImplTest.cpp
index 23c30ce..af8ed08 100644
--- a/tests/test-tsqsim/src/TSXformImplTest.cpp
+++ b/tests/test-tsqsim/src/TSXformImplTest.cpp
@@ -37,15 +37,16 @@ TEST(Conv_inv)
     for (int itype = 0; itype < int(TSXformType::END); ++itype)
     {
         const TSXformType type = TSXformType(itype);
-        const Str xformStr = xform2str.at(itype);
+        Str xformStr = xform2str.at(itype);
         if (verbose)
         {
             LOGL << xformStr << Nl;
         }
-        if (type == TSXformType::ADD)
+        if (type == TSXformType::ADD ||
+            type == TSXformType::MUL ||
+            type == TSXformType::DIV )
         {
-            /// TODO: Uses a different constructor
-            continue;
+            xformStr += " 3"; // Expects a parameter
         }
         CorPtr<ITSXform> xform = TSXformFactory().Create(xformStr);
         
@@ -56,8 +57,6 @@ TEST(Conv_inv)
             break;        /// TODO: Probably the most important
         case TSXformType::FABS:
             break;
-        case TSXformType::ADD:
-            break;
         default:
             {
                 for (int i = 0; i < int(inp.size()); ++i)
@@ -82,7 +81,7 @@ TEST(Conv_diffs)
     /// TODO: TSXformType::DIFF:
 }
 
-TEST(Conv_add)
+TEST(Conv_fabs)
 {
-    /// TODO: TSXformType::ADD:
+    /// TODO: TSXformType::FABS:
 }
\ No newline at end of file