diff --git a/src/storage/storage_device.rs b/src/storage/storage_device.rs
index a41085c..098b241 100644
--- a/src/storage/storage_device.rs
+++ b/src/storage/storage_device.rs
@@ -75,8 +75,7 @@ impl<'a> StorageDevice<'a> {
             .chars()
             .rev()
             .next()
-            .expect("Storage device name is empty")
-            .is_digit(10)
+            .expect("Storage device name is empty").is_ascii_digit()
         {
             format!("{}p{}", self.name, index)
         } else {