To ensure your Amsterdam poppers stay as fresh as long as possible, store them upright as soon as they arrive. While a few days in transit will be fine, the chemicals in poppers are corrosive and will eventually dissolve the sealant placed around the lid. This will also help avoid any leakages.  To ensure we only send you fresh bottles, we keep limited stock ourselves. To keep them this way we also recommend keeping them refrigerated, or at the very least somewhere dark and not too warm.