Sustainable cannabis inside and out! Buy any Preserve cartridge from Purextracts get the 2nd for 50% off! ($33.50 savings on the purchase of two cartridges). Rediscover the strains you love with Preserve, a new cartridge featuring single-origin, perfectly cured, 100% cannabis oil and cannabis-derived terpenes. True-To-Flower Cured Cannabis Cartridge ™ Pure Cannabis. No Fillers.