Spanx BoostUp Cropped Square Neck Shelf Tank Top Fuchsia Ghelamco Group. Boost more than just your confidence with the SPANX BoostUp Cropped Square Neck Shelf Tank. Crafted from our breathable, sweat wicking, sleek and sporty FlexAppeal performance fabricplus 4 way stretch for maximum comfort. This cropped active tank features a built in shelf bra with removable cups for customizable support. Designed for both high performance and style, this tank is made to move.