GB Capacity Description: 8GB=approx. 7.3GB-7.6GB 16GB=approx. 14GB-15GB 32GB=approx. 28GB-29GB 64GB=approximately 57GB-59GB 128GB=approximately 118GB-120GB This is the difference in calculation between the manufacturer and your PC, please google "storage product capacity" for more information. 1GB as defined by PC = 1,073,741,824,000,000 bytes, while 1GB as defined by the market = 1,000,000,000,000 bytes 100% real capacity by H2testw. Please do not use cheap card readers for testing, the speed will be reduced due to low quality readers. Product Description: Name: TF Card Capacity: 8GB C10 16GB C10 32GB U1 64GB U3 128GB U1 128GB U3 Material: Epoxy resin Speed: Read 70MB / s, write 20MB / s Applicable devices: Desktop computers, laptops, surveillance equipment, cameras, cell phones Operating temperature: - 13F to 185F (- 25C to 85C) Storage temperature: - 40F to 185F (- 40C to 85C) Size: 15*11*1mm Weight: 5.3g Package includes: 1X TF card Notes on use: Note actual capacity: 8GB=approx. 7.3GB-7.6GB 16GB=approx. 14GB-15GB 32GB=approx. 28GB-29GB 64GB=approximately 57GB-59GB 128GB=approximately 118GB-120GB This is a calculated difference between the manufacturer and your PC, please google "storage product capacity" for more information. 1GB as defined by PC = 1,073,741,824,000,000 bytes, while 1GB as defined by the market = 1,000,000,000,000 bytes 100% true capacity by H2testw. Please do not use cheap card readers for testing, the speed will be reduced due to low quality readers.