Adjustable strap, backless. It's very sexy with high slit. Great for any cup size.  May be worn with an adhesive bra, petals, or no bra. I am 5.3 high and wearing 3 inches heels. Worn once only for the occasion where I took those first two photos. Dry cleaned for sale. Excellent condition. Downsizing my closest. I can post more photos upon request.