Amazon.com: Sonic Acoustics 12 Pack Acoustic Foam Panels 0.4" X 12" X 12" Sound Absorbing Panel, 3D Unique Soundproof Foam Insulation, Foam Padding Used in Home & Offices (12 Pack, White) :
Soundproof Cow - Class A Acoustic Foam Panel 1"
SONEX Acoustical Pyramid Panels in Natural White - 4" x 2' x 2'
Soundproof Cow - Udderly Quiet™ Class A™ Anechoic Acoustic Foam 4" White (Case of 4)
White Mela-Foam Pyramid Acoustic Panels – Sundance Acoustics