diff --git a/src/flow/binary/bounds.rs b/src/flow/binary/bounds.rs
index 1f7917d..0e96553 100644
--- a/src/flow/binary/bounds.rs
+++ b/src/flow/binary/bounds.rs
@@ -70,7 +70,7 @@ impl<A: Clone> Bounds<A> {
         Self::new(l.l, r.r, comparator)
     }
 
-    pub fn equal_bound(l: &Option<A>, r: &Option<A>, comparator: &impl Comparator<A>) -> bool {
+    fn equal_bound(l: &Option<A>, r: &Option<A>, comparator: &impl Comparator<A>) -> bool {
         match (l, r) {
             (None, None) => true,
             (Some(kl), Some(kr)) => matches!(comparator.pick_smaller(kl, kr), Comparison::E),