Size: 4 oz capacity. Product benefits: Glass is infinitely recyclable. Freezer safe. Microwave safe. Tempered glass is 5x stronger than regular glass. Impermeable glass. Will not leach or stain. Chemical-free (no BPA, PVC, lead, phthalates or other nasty chemicals). Smart clips are easy for everyone to open. Silicone seals create water and airtight. Seal to prevent leaks and keep food fresh.