diff --git a/src/notify/mod.rs b/src/notify/mod.rs
index 1803b21..557ae93 100644
--- a/src/notify/mod.rs
+++ b/src/notify/mod.rs
@@ -230,11 +230,11 @@ pub enum NotifyState<'a> {
     /// Tell the service manager to execute the configured watchdog option.
     WatchdogTrigger,
     /// Reset watchdog timeout value during runtime.
-    /// The value is in milliseconds.
-    WatchdogUsec(types::Milliseconds),
+    /// The value is in microseconds.
+    WatchdogUsec(types::Microseconds),
     /// Tells the service manager to extend the startup, runtime or shutdown service timeout corresponding the current state.
-    /// The value is in milliseconds.
-    ExtendTimeoutUsec(types::Milliseconds),
+    /// The value is in microseconds.
+    ExtendTimeoutUsec(types::Microseconds),
 }
 
 impl<'a> Display for NotifyState<'a> {
@@ -254,10 +254,10 @@ impl<'a> Display for NotifyState<'a> {
             NotifyState::Stopping => f.write_str("STOPPING=1"),
             NotifyState::Watchdog => f.write_str("WATCHDOG=1"),
             NotifyState::WatchdogTrigger => f.write_str("WATCHDOG=trigger"),
-            NotifyState::WatchdogUsec(types::Milliseconds(milliseconds)) => {
+            NotifyState::WatchdogUsec(types::Microseconds(milliseconds)) => {
                 write!(f, "WATCHDOG_USEC={milliseconds}")
             }
-            NotifyState::ExtendTimeoutUsec(types::Milliseconds(milliseconds)) => {
+            NotifyState::ExtendTimeoutUsec(types::Microseconds(milliseconds)) => {
                 write!(f, "EXTEND_TIMEOUT_USEC={milliseconds}")
             }
         }
diff --git a/src/notify/types.rs b/src/notify/types.rs
index cd5392b..d260d16 100644
--- a/src/notify/types.rs
+++ b/src/notify/types.rs
@@ -70,16 +70,17 @@ impl AsRef<str> for StatusLine<'_> {
     }
 }
 
+/// Semantic type representing a number of microseconds.
 #[derive(Debug, Clone, Copy, PartialEq, Eq, Hash)]
-pub struct Milliseconds(pub(super) u64);
+pub struct Microseconds(pub(super) u64);
 
-impl From<u64> for Milliseconds {
+impl From<u64> for Microseconds {
     fn from(value: u64) -> Self {
         Self(value)
     }
 }
 
-impl AsRef<u64> for Milliseconds {
+impl AsRef<u64> for Microseconds {
     fn as_ref(&self) -> &u64 {
         &self.0
     }