Chicco's manual for the Chicco MyFit Zip sets a life of 8 years. The seat's label gives the exact "Do Not Use After" date.
What the maker says:
DO NOT use this Child Restraint if it is more than 8 years old. Check manufacturer’s label on underside of Child Restraint for the “Do Not Use After” date.
Source: www.chiccousa.com, checked 2026-10-24.
Look up another model, or work out the date from a manufacture date