What kind of foam is pillow made of?

The pillows consist of a removable cover with a zipper on the rear side and heat-resistant hard polyurethane foam or soft memory foam inserts.

The heat-resistant foam insert passed tests GB 18401-410 and GB  6675.4-2014 for hazardous materials absence.

• Formaldehyde <20mg/kg ( standard <70 )
• As <5mg/kg ( standard <25 )
• Ba <10mg/kg ( standard <1000 )
• Cd <5mg/kg ( standard <75 )
• Hr <5mg/kg ( standard <60 )
• Hg <5mg/kg ( standard <60 )
• Pb <10mg/kg ( standard <90 )
• Sb <5mg/kg ( standard <60 )
• Se <10mg/kg ( standard <500 )

If you are not sure that you will need a Hard pillow for cervical support, it may be better to choose the Soft one because it is more comfortable.