diff --git a/crates/cgp-field/src/types/index.rs b/crates/cgp-field/src/types/index.rs
index a2938e7..f7ecc09 100644
--- a/crates/cgp-field/src/types/index.rs
+++ b/crates/cgp-field/src/types/index.rs
@@ -1 +1,9 @@
+use core::fmt::Display;
+
 pub struct Index<const I: usize>;
+
+impl<const I: usize> Display for Index<I> {
+    fn fmt(&self, f: &mut core::fmt::Formatter<'_>) -> core::fmt::Result {
+        write!(f, "{I}")
+    }
+}