diff --git a/src/page_pool.rs b/src/page_pool.rs
index cc50b30..5161ae7 100644
--- a/src/page_pool.rs
+++ b/src/page_pool.rs
@@ -93,6 +93,8 @@
 
 impl Region for Pages {
     type Resource = ();
+    type Base = usize;
+    type Length = usize;
 
     fn base(&self) -> usize {
         self.pa