diff --git a/src/main/kotlin/com/cubetiqs/libra/moneyutils/MoneyExtension.kt b/src/main/kotlin/com/cubetiqs/libra/moneyutils/MoneyExtension.kt
new file mode 100644
index 0000000..05caf96
--- /dev/null
+++ b/src/main/kotlin/com/cubetiqs/libra/moneyutils/MoneyExtension.kt
@@ -0,0 +1,3 @@
+package com.cubetiqs.libra.moneyutils
+
+fun StdMoney
\ No newline at end of file
diff --git a/src/main/kotlin/com/cubetiqs/libra/moneyutils/MoneyOperator.kt b/src/main/kotlin/com/cubetiqs/libra/moneyutils/MoneyOperator.kt
index 83f1bb8..f9a15df 100644
--- a/src/main/kotlin/com/cubetiqs/libra/moneyutils/MoneyOperator.kt
+++ b/src/main/kotlin/com/cubetiqs/libra/moneyutils/MoneyOperator.kt
@@ -1,13 +1,12 @@
 package com.cubetiqs.libra.moneyutils
 
-operator fun Money.unaryMinus() = (-getMoneyValue())
-operator fun Money.unaryPlus() = (+getMoneyValue())
+operator fun StdMoney.unaryMinus() = (-getMoneyValue())
+operator fun StdMoney.unaryPlus() = (+getMoneyValue())
 operator fun Money.inc() = Money(value++)
 operator fun Money.dec() = Money(value--)
-operator fun Money.plus(other: Money) = Money(value + other.value)
-operator fun Money.times(other: Money) = Money(value * other.value)
-operator fun Money.div(other: Money) = Money(value / other.value)
-operator fun Money.timesAssign(other: Money) {
-    this.value = this.value * other.value
-}
-operator fun Money.not() = this.value != this.value
\ No newline at end of file
+operator fun StdMoney.plus(other: StdMoney) = Money(getMoneyValue() + other.getMoneyValue())
+operator fun StdMoney.times(other: StdMoney) = Money(getMoneyValue() * other.getMoneyValue())
+operator fun StdMoney.div(other: StdMoney) = Money(getMoneyValue() / other.getMoneyValue())
+operator fun Money.timesAssign(other: StdMoney) {
+    this.value = this.getMoneyValue() * other.getMoneyValue()
+}
\ No newline at end of file