So I ordered a Bellaband from Ingrid and Isobel when my jeans stopped buttoning, but quickly switched back to using a hair tie/rubber band again because it slips (even the one with the non-slip silicone piece). The only this is, a rubber band didn't work too well with dress pants because of the double button/hook thing. I got this from Motherhood mostly for the dress pants hook extender, and love it! It was $20 and worth it.  Also, I definitely reccomend Motherhood for maternity shopping. Great stuff, great sales, and if you sign up for their coupon list, you also get coupons for places like Buy buy baby and Carters, and for other stuff like formula and diapers.