Severance offer, what should I ask for? after 15 years as a production planner

I was offered 15 weeks of severance after 15 years as a production planner, and I have a few days to sign. I do not usually post, so bear with me. It includes health coverage for a couple of months. What did you ask for?

Ask for the offer in writing and do not sign on the spot. A day or two to think is normal.