Thank you for sharing us this information. We will have our engineers compare and verify the dimensions before making the necessary changes. We will get back to you soon.
Thank you for patiently waiting. Our engineers have checked both parts and although they may look the same, there are some measurements that are different.
Since our engineer thought that we already have a base model(APDS-9960) and there are only small differences with the RPR-0521RS part, he recreated the 3D model and uploaded it to the part page. You can now download it here: https://www.snapeda.com/parts/RPR-0521RS/Rohm/view-part/
Let me know if you have any questions about it.