This set is made from BPA-free Borosilicate glass, safe for microwaves and ovens up to 600 degrees. It includes snap-locking plastic lids with a 4-hinge locking latch to prevent leaks. It comprises 10 glass containers designed for versatile food storage. Price drops from $49.99 to just $22.99. Shipping is free with Amazon Prime or is otherwise a flat $6 per order.