It's simple physics, just ask Isaac Newton,  if you want to keep something from falling "suspend" it from a fixed position. Got it Mr. Slouchy Pants, if you want your pants to really stay up, try a pair of big boy suspenders or as the Brits call them, Braces, for a truly polished look. 

1 3/8" Woven Heathered Black Herringbone Elastic

Matching Lower Back Strap

Black Leather Joiner and Button-on Ends 

Silver Hardware 

 MADE IN BK, NEW YORK - USA