Most cartridges could be refilled with the own THC oil, CBD vape oil or e-liquid before you decide to want to remove them. If it’s a 510 design cartridge, just unscrew the mouthpiece and fill the tank up. You may have to work with a syringe for precision. Retailer upright: https://stepheninzdk.dailyhitblog.com/38108121/thc-cartridges-things-to-know-before-you-buy