diff --git a/Cargo.toml b/Cargo.toml
index 6131b0c..872ed09 100644
--- a/Cargo.toml
+++ b/Cargo.toml
@@ -16,7 +16,7 @@ members = [
 ]
 
 [workspace.package]
-version = "0.4.1"
+version = "0.4.2"
 edition = "2021"
 repository = "https://git.bfpower.io/BFPOWER/physical"
 readme = "README.md"
diff --git a/src/quantity/mod.rs b/src/quantity/mod.rs
index b8255ff..1ab7f87 100644
--- a/src/quantity/mod.rs
+++ b/src/quantity/mod.rs
@@ -2,6 +2,7 @@ mod irradiance;
 mod resistance;
 mod temperature;
 mod voltage;
+mod volume;
 mod volume_rate;
 mod pressure;
 
@@ -12,6 +13,7 @@ pub use irradiance::*;
 pub use resistance::*;
 pub use temperature::*;
 pub use voltage::*;
+pub use volume::*;
 pub use volume_rate::*;
 pub use pressure::*;
 
diff --git a/src/quantity/temperature.rs b/src/quantity/temperature.rs
index 745fd49..60bef1d 100644
--- a/src/quantity/temperature.rs
+++ b/src/quantity/temperature.rs
@@ -21,7 +21,7 @@ impl <V: Value> Kelvins<V> {
     }
 }
 
-//----- Deci Kelvins ----------------------------------
+//----- Decikelvins ----------------------------------
 quantity_type! {DeciKelvins, "dK"}
 
 impl<V: Value> DeciKelvins<V> {
diff --git a/src/quantity/voltage.rs b/src/quantity/voltage.rs
index f7e12ed..f086d49 100644
--- a/src/quantity/voltage.rs
+++ b/src/quantity/voltage.rs
@@ -14,7 +14,7 @@ impl<V: Value> Volts<V> {
     }
 }
 
-//----- Milli Volts ----------------------------------
+//----- Millivolts ----------------------------------
 quantity_type! {MilliVolts, "mV"}
 
 impl<V: Value> MilliVolts<V> {
diff --git a/src/quantity/volume.rs b/src/quantity/volume.rs
new file mode 100644
index 0000000..a482487
--- /dev/null
+++ b/src/quantity/volume.rs
@@ -0,0 +1,43 @@
+use crate::quantity::{Quantity, Value};
+use generate_quantity::quantity_type;
+
+use crate::quantity::MILLI;
+
+//----- Liters ----------------------------------
+quantity_type! {Liters, "L"}
+
+impl<V: Value> Liters<V> {
+    #[inline]
+    pub fn to_milli_liters(self) -> MilliLiters<V> {
+        let multiplier = V::from_u16(MILLI).unwrap();
+        MilliLiters(self.0 * multiplier)
+    }
+}
+
+//----- Milliliters ----------------------------------
+quantity_type! {MilliLiters, "mL"}
+
+impl<V: Value> MilliLiters<V> {
+    #[inline]
+    pub fn to_liters(self) -> MilliLiters<V> {
+        let divisor = V::from_u16(MILLI).unwrap();
+        MilliLiters(self.0 / divisor)
+    }
+}
+
+// ---------------------------------------------------------------------------------------------------------------------
+// ----- Tests ------------------------
+// ---------------------------------------------------------------------------------------------------------------------
+#[cfg(test)]
+mod tests {
+    use super::*;
+
+    #[test]
+    fn convert_u32() {
+        let liters: Liters<u32> = 12.liters();
+        let milli_liters: MilliLiters<u32> = 12_000.milli_liters();
+
+        assert_eq!(liters.0, milli_liters.to_liters().0);
+        assert_eq!(milli_liters.0, liters.to_milli_liters().0);
+    }
+}