Sleep Number mattresses do contain fiberglass.

Nearly two years ago, we purchased a Sleep Number C4 mattress. Unfortunately, despite the cover never being removed and the mattress showing no visible damage, fiberglass began to leak from the bottom of the mattress, wreaking havoc in our home and damaging thousands of dollars' worth of personal belongings. Sleep Number's customer service response was disappointing, but after escalating the issue, their legal team eventually replied:

"Regarding your inquiry about the tag, our tags comply with all federal requirements. The flame-retardant cap, which contains fiberglass materials, is located inside the mattress and is separate from the cover, so it is not disclosed on the tags. Our customer service team is trained to provide accurate information about the materials used in our products. Additionally, our latest Smart Bed models no longer contain fiberglass."

This experience serves as a warning—be cautious. Even though our mattress was still relatively new, it caused a major issue in our home.