Larsen Z Bra in Black. Size: Medium. Meet our best seller that has sold out 6 times! With a focus on premium comfort, the Larken X is an all-in-one nursing and hands-free pumping bra made with lightweight buttery smooth stretch fabric that adapts to your changing breast size. Designed to make your life easier, the Larken X is wire-free with relaxed support and skips the weird holes, elastic, zippers or clips — making it the most comfortable, easy to use nursing and pumping bra you'll want to live in day and night. 90% polyester, 10% spandex.