Untitled 1PROMASTER RUGGED MEMORY CARDS are designed to keep your memories safe Their world-proof design is the result of a unique manufacturing process making the cards up to 3 times stronger than other products. Industrial grade internal components offer maximum protection against water, high humidity, extreme heat and cold, as well as impact. RUGGED memory is simply the strongest storage available for your irreplaceable memories64GB SDXC660X99MB/s Read Speed80MB/s Write SpeedUHS-1 Speed class 3, U3Operating temperature range: -13 to 185F (-25 to 85C)