diff --git a/types/p2/index.d.ts b/types/p2/index.d.ts
index 40cee3c1d6..5db3397ae7 100644
--- a/types/p2/index.d.ts
+++ b/types/p2/index.d.ts
@@ -760,16 +760,13 @@ declare namespace p2 {
 
     }
 
-    export class Box extends Shape {
+    export class Box extends Convex {
 
         constructor(options?: BoxOptions);
 
         width: number;
         height: number;
 
-        computeMomentOfInertia(mass: number): number;
-        updateArea(): void;
-
     }
 
     export interface CapsuleOptions extends SharedShapeOptions {