Firmness

13 psi
21 psi
3 psi
6 psi
Extra Soft
Extra Soft (0 - 4 psi)
Extra Soft (0 to 4 psi)
Firm
Firm (14+ psi)
Firm (?14 psi)
Firm (??????14 psi)
Medium
Medium (9 - 13 psi)
Medium (9 to 13 psi)
Soft
Soft (5 - 8 psi)
Soft (5 to 8 psi)