Storage vessels are optimised for minimum evaporation during prolonged stationary use. They have wide-mouth necks for canister access and are not designed for movement while charged with liquid nitrogen. Transport dewars, sometimes called dry shippers, absorb liquid nitrogen into an internal sorbent matrix so they can be tilted, inverted, and shipped by courier without spillage. Dry shippers maintain cryogenic temperatures for 5 to 10 days depending on model and ambient conditions. Cryolab stocks both categories, and the correct choice depends entirely on whether samples are being stored on-site or shipped between facilities.