For affordability 16GB, 32GB and 64GB cards are most popular. USB Flash Drives come in many different colors, with or without caps. Sometimes the USB connector is retractable, sliding inside the drive housing for protection when not in use, or covered by a cap of swivel. USB flash drives are very popular in the promotional and educational spaces where customer logos are printed on the drive. The first USB Flash Drive patent was filed in 1999 by Israeli company M-Systems, a business later acquired by Sandisk. The first USB Flash Drives sold in America were made by IBM.