diff --git a/src/drawing/band.rs b/src/drawing/band.rs
index 202d9d9..3fb44c7 100644
--- a/src/drawing/band.rs
+++ b/src/drawing/band.rs
@@ -1,4 +1,15 @@
-use crate::drawing::seg::{LoneLooseSegIndex, SeqLooseSegIndex};
+use crate::{
+    drawing::seg::{LoneLooseSegIndex, SeqLooseSegIndex},
+    geometry::shape::MeasureLength,
+    graph::MakeRef,
+};
+
+use super::{
+    dot::DotIndex,
+    primitive::{GetJoints, GetOtherJoint},
+    rules::AccessRules,
+    Drawing,
+};
 
 #[derive(Debug, Hash, Clone, Copy, Eq, PartialEq)]
 pub enum BandFirstSegIndex {
@@ -6,4 +17,55 @@ pub enum BandFirstSegIndex {
     Bended(SeqLooseSegIndex),
 }
 
-pub struct BandRef {}
+impl<'a, CW: Copy, R: AccessRules> MakeRef<'a, BandRef<'a, CW, R>, Drawing<CW, R>>
+    for BandFirstSegIndex
+{
+    fn ref_(&self, drawing: &'a Drawing<CW, R>) -> BandRef<'a, CW, R> {
+        BandRef::new(*self, drawing)
+    }
+}
+
+pub struct BandRef<'a, CW: Copy, R: AccessRules> {
+    first_seg: BandFirstSegIndex,
+    drawing: &'a Drawing<CW, R>,
+}
+
+impl<'a, CW: Copy, R: AccessRules> BandRef<'a, CW, R> {
+    pub fn new(first_seg: BandFirstSegIndex, drawing: &'a Drawing<CW, R>) -> BandRef<'a, CW, R> {
+        Self { first_seg, drawing }
+    }
+}
+
+impl<'a, CW: Copy, R: AccessRules> MeasureLength for BandRef<'a, CW, R> {
+    fn length(&self) -> f64 {
+        match self.first_seg {
+            BandFirstSegIndex::Straight(seg) => {
+                self.drawing.geometry().seg_shape(seg.into()).length()
+            }
+            BandFirstSegIndex::Bended(start_seg) => {
+                let mut length = self.drawing.geometry().seg_shape(start_seg.into()).length();
+                let start_dot = self.drawing.primitive(start_seg).joints().1;
+
+                let bend = self.drawing.primitive(start_dot).bend();
+                length += self.drawing.geometry().bend_shape(bend.into()).length();
+
+                let mut prev_dot = self.drawing.primitive(bend).other_joint(start_dot.into());
+                let mut seg = self.drawing.primitive(prev_dot).seg().unwrap();
+                length += self.drawing.geometry().seg_shape(seg.into()).length();
+
+                while let DotIndex::Loose(dot) =
+                    self.drawing.primitive(seg).other_joint(prev_dot.into())
+                {
+                    let bend = self.drawing.primitive(dot).bend();
+                    length += self.drawing.geometry().bend_shape(bend.into()).length();
+
+                    prev_dot = self.drawing.primitive(bend).other_joint(dot);
+                    seg = self.drawing.primitive(prev_dot).seg().unwrap();
+                    length += self.drawing.geometry().seg_shape(seg.into()).length();
+                }
+
+                length
+            }
+        }
+    }
+}
diff --git a/src/layout/layout.rs b/src/layout/layout.rs
index 94cd28b..14c3eff 100644
--- a/src/layout/layout.rs
+++ b/src/layout/layout.rs
@@ -208,38 +208,6 @@ impl<R: AccessRules> Layout<R> {
         self.drawing.remove_band(band);
     }
 
-    pub fn band_length(&self, band: BandFirstSegIndex) -> f64 {
-        match band {
-            BandFirstSegIndex::Straight(seg) => {
-                self.drawing.geometry().seg_shape(seg.into()).length()
-            }
-            BandFirstSegIndex::Bended(start_seg) => {
-                let mut length = self.drawing.geometry().seg_shape(start_seg.into()).length();
-                let start_dot = self.drawing.primitive(start_seg).joints().1;
-
-                let bend = self.drawing.primitive(start_dot).bend();
-                length += self.drawing.geometry().bend_shape(bend.into()).length();
-
-                let mut prev_dot = self.drawing.primitive(bend).other_joint(start_dot.into());
-                let mut seg = self.drawing.primitive(prev_dot).seg().unwrap();
-                length += self.drawing.geometry().seg_shape(seg.into()).length();
-
-                while let DotIndex::Loose(dot) =
-                    self.drawing.primitive(seg).other_joint(prev_dot.into())
-                {
-                    let bend = self.drawing.primitive(dot).bend();
-                    length += self.drawing.geometry().bend_shape(bend.into()).length();
-
-                    prev_dot = self.drawing.primitive(bend).other_joint(dot);
-                    seg = self.drawing.primitive(prev_dot).seg().unwrap();
-                    length += self.drawing.geometry().seg_shape(seg.into()).length();
-                }
-
-                length
-            }
-        }
-    }
-
     pub fn polys<W: 'static>(
         &self,
         node: GenericIndex<W>,
diff --git a/tests/common/mod.rs b/tests/common/mod.rs
index b70679c..37908a5 100644
--- a/tests/common/mod.rs
+++ b/tests/common/mod.rs
@@ -9,7 +9,8 @@ use topola::{
     },
     board::{mesadata::AccessMesadata, Board},
     drawing::graph::{GetLayer, GetMaybeNet},
-    graph::GetPetgraphIndex,
+    geometry::shape::MeasureLength,
+    graph::{GetPetgraphIndex, MakeRef},
     specctra::{design::SpecctraDesign, mesadata::SpecctraMesadata},
 };
 
@@ -148,7 +149,7 @@ pub fn assert_band_length(
     epsilon: f64,
 ) {
     let band = board.band_between_pins(source, target).unwrap();
-    let band_length = board.layout().band_length(band);
+    let band_length = band.ref_(board.layout().drawing()).length();
     assert!((band_length - length).abs() < epsilon);
 }