diff --git a/src/stores/useModelStore.ts b/src/stores/useModelStore.ts
index 9aeb10c..6596eb3 100644
--- a/src/stores/useModelStore.ts
+++ b/src/stores/useModelStore.ts
@@ -133,6 +133,8 @@ export interface MeasurePoint {
   x: number;
   y: number;
   z: number;
+  /** Model hit by this point, used so saved dimensions attach to the right piece. */
+  modelId?: string;
 }
 
 export interface Measurement {
@@ -153,6 +155,7 @@ export interface HoverInfo {
   type: 'hole' | 'edge';
   position: [number, number, number];
   value: number; // mm (diameter or length)
+  modelId?: string;
   /** For edges: the two endpoints in world coords. */
   endpoints?: { a: MeasurePoint; b: MeasurePoint };
 }