Billabong Tanlines Surf Tank Bikini Top. The Billabong Tanlines Surf Tank Bikini Top is made for active beach days, blending a sporty look with a secure, comfortable fit. Designed with a tank-style silhouette, it features a flattering scoop neckline and wide shoulder straps that provide extra support without digging in. The soft ribbed fabric feels smooth against the skin while offering enough stretch and strength to move with you in and out of the water. Fully lined for added comfort and coverage and finished with adjustable straps for a personalized fit, this top stays put so you can focus on the fun. 91% Recycled Polyester 9% Spandex. Lining: 92% Recycled Polyester 8% Spandex. Hand wash. Imported.