diff --git a/src/tool.rs b/src/tool.rs
index 76b59099..1fe43cb6 100644
--- a/src/tool.rs
+++ b/src/tool.rs
@@ -2,19 +2,19 @@
 
 pub trait Format {
     /// Format bytes to KB/MB/GB presentation
-    fn bytes(&self) -> String;
+    fn bytes(self) -> String;
 }
 
 impl Format for usize {
-    fn bytes(&self) -> String {
+    fn bytes(self) -> String {
         const KB: f32 = 1024.0;
         const MB: f32 = KB * KB;
         const GB: f32 = MB * KB;
 
-        let f = *self as f32;
+        let f = self as f32;
 
         if f < KB {
-            format!("{self} {}", plurify::ns(*self, &["byte", "bytes", "bytes"]))
+            format!("{self} {}", plurify::ns(self, &["byte", "bytes", "bytes"]))
         } else if f < MB {
             format!("{:.2} KB", f / KB)
         } else if f < GB {