To ensure product safety and quality, RELX pods are not designed to be reused or refilled and should not be opened. Opening or otherwise tampering with the pod will render the warranty on the pod null and void.
RELX Classic device is made of aluminum alloy with high strength and endurance. The shell material of cartridge is PCTG produced by Eastman in the US, which is mostly used to make aviation cups, milk bottle, etc. It is resistant to high temperature and will not release harmful substances, thus you can use it without any worries.