Manfrotto Bogen Pack Of 3 X 8' Black Stacker Stands +015 1052BAC-3 Manfrotto 2 Year Warranty (Additional 3 Years with Online Registration) Quick Stack System: With the patented Quick Stack System (QSS), portability is the key feature. Clip the stands together and save a lot of room in the studio, or carry them in a compact case to easily bring them with you for outdoor shooting. Stacking System Leg Lock: A stronger and more ergonomic handle makes it easier/assists to secure stands into the operating position. Locking Device: Push on the locking device and detach one stand, for quick usage Attachment: A 3/8'' screw top female to 1/4" adapter male (015), allows you to connect additional accessories.