diff --git a/crates/pptx/src/write/shapes.rs b/crates/pptx/src/write/shapes.rs
index e799ea84f..b211e265f 100644
--- a/crates/pptx/src/write/shapes.rs
+++ b/crates/pptx/src/write/shapes.rs
@@ -106,7 +106,9 @@ pub fn geometry(w: &mut W, g: &Geom) {
                 let single = !adj1 && if defaults.is_empty() { vals.len() == 1 } else { defaults.len() == 1 };
                 for (i, v) in vals.iter().enumerate() {
                     let n = if single && i == 0 { "adj".to_string() } else { format!("adj{}", i + 1) };
-                    let v = if v.is_finite() { v.round().clamp(-2.0e9, 2.0e9) as i64 } else { 0 };
+                    // A near-zero-width connector can need a large ratio for an ordinary-size bend.
+                    // Keep guide literals bounded to the signed integer serialization domain.
+                    let v = if v.is_finite() { v.round().clamp(i64::MIN as f64, i64::MAX as f64) as i64 } else { 0 };
                     w.empty("a:gd", A::new().a("name", n).a("fmla", format!("val {v}")));
                 }
                 for (n, v) in extra_guides(name) {
@@ -1031,6 +1033,23 @@ pub fn tree_header(w: &mut W) {
 mod tests {
     use super::*;
 
+    #[test]
+    fn guide_literals_remain_finite_bounded_integers() {
+        for (guide, expected) in [
+            (f64::NAN, 0),
+            (f64::INFINITY, 0),
+            (f64::NEG_INFINITY, 0),
+            (f64::MAX, i64::MAX),
+            (f64::MIN, i64::MIN),
+            (12500.6, 12501),
+            (-12500.6, -12501),
+        ] {
+            let mut w = W::frag();
+            geometry(&mut w, &Geom::Preset { name: "bentConnector3".into(), adj: vec![guide] });
+            assert!(w.s.contains(&format!(r#"fmla="val {expected}""#)), "{}", w.s);
+        }
+    }
+
     /// PowerPoint asks to repair a `star5` whose guide list lacks `hf`/`vf` (found black-box).
     #[test]
     fn preset_guides_are_complete() {
diff --git a/crates/pptx/tests/it/roundtrip.rs b/crates/pptx/tests/it/roundtrip.rs
index f44b0c152..e13947669 100644
--- a/crates/pptx/tests/it/roundtrip.rs
+++ b/crates/pptx/tests/it/roundtrip.rs
@@ -1396,6 +1396,45 @@ fn single_guide_names_follow_the_preset() {
     }
 }
 
+/// Large finite guides position a visible bend even when the connector is only one EMU wide.
+#[test]
+fn large_connector_adjustments_keep_their_elbows_through_two_saves() {
+    let cases = [
+        ("ordinary", 80.0, 50000.0),
+        ("near control", 1588.0 / 12700.0, -12800000.0),
+        ("near negative", 1.0 / 12700.0, -20320000000.0),
+        ("near positive", 1.0 / 12700.0, 20320000000.0),
+        ("zero width", 0.0, 20320000000.0),
+        ("ordinary negative", 80.0, -20000.0),
+    ];
+    let mut p = defaults::new_presentation(None);
+    p.slides.clear();
+    let mut s = new_slide(&mut p, "Connectors");
+    s.shapes.clear();
+    for (name, width, guide) in cases {
+        let mut sh = shape(&mut p, name, 100.0, 80.0, width, 140.0);
+        sh.kind = ShapeKind::Connector { start: None, end: None };
+        sh.geom = Geom::Preset { name: "bentConnector3".into(), adj: vec![guide] };
+        s.shapes.push(sh);
+    }
+    p.slides.push(Arc::new(s));
+    for generation in 1..=2 {
+        p = deckcraft_pptx::import(&deckcraft_pptx::export(&p).expect("export")).expect("reopen");
+        for (name, width, guide) in cases {
+            let sh = p.slides[0].shapes.iter().find(|sh| sh.name == name).expect("connector");
+            let Geom::Preset { name: preset, adj } = &sh.geom else {
+                panic!("preset connector");
+            };
+            assert_eq!(adj, &[guide], "{name}, save {generation}");
+            let xfrm = sh.xfrm.expect("transform");
+            assert_eq!((xfrm.w, xfrm.h), (width, 140.0));
+            let expected = deckcraft_geom::preset::build("bentConnector3", width, 140.0, &[guide]).expect("expected geometry");
+            let actual = deckcraft_geom::preset::build(preset, xfrm.w, xfrm.h, adj).expect("reopened geometry");
+            assert_eq!(actual.outline(), expected.outline(), "{name}, save {generation}");
+        }
+    }
+}
+
 /// #147: PowerPoint's Float Down is preset 47 (Float Up is 42); it imported as a plain fade.
 #[test]
 fn float_down_is_preset_47_both_ways() {