A:Answer Hi Tivaal!
Thank you for reaching out to us. We appreciate your interest in knowing if Galaxy S21 Ultra S Pen works with Galaxy Tab A7. We apologize, Galaxy S21 Ultra S Pen is compatible with Galaxy S21 Ultra 5G only.
For more information about the Galaxy S21 Ultra S Pen, you may visit our website: https://www.samsung.com/us/mobile/mobile-accessories/phones/galaxy-s21-ultra-5g-s-pen-ej-pg998bbegus/.
Should you need more assistance, please feel free to get back to us via the following options:
1. Facebook Messenger: http://m.me/samsungsupport
2. Twitter: https://twitter.com/messages/compose?recipient_id=18768513
3. Samsung Community: https://us.community.samsung.com/t5/Samsung-Community/ct-p/us
Reference #: 1144267609
Have a great day.
Melardo