Genicook glass meal and food containers are made of highly durable borosilicate glass that can easily handle temperatures of up to +560C/ +1040F and down to -40C/ -40F. The 8 piece set includes 4 lids & 4 glass containers. Square shape: 17.6 oz/ 2.2 cup, 27.0 oz/ 3.4 cup, 10.8 oz/ 1.4 cup, 10.8 oz/1.4 cup. Detachable lid snaps are durable and unbreakable, even in low temperatures. The lids are vented, making it convenient to release steam. The silicone wrap fully covers the corners to help protect the glass from breakage.