Lastin

Lastin - Clear Elastic - 5 yards
product from Ready-To-Wear 

5 yard package, 3/8" wide
Perfect for use when finishing with a serger - as if you 'cut' into it, the elastic isn't DEAD! 
Londa says:  "I use by laying a hair inside the edge on the WRONG side of the fabric, machine set at a big, wide zig zag, and pull ever so slightly on the elastic as it feeds in. Then - serge off excess, with elastic up so you can see it at the serger. Then - turn to inside and stitch. I like the looks of a twin needle stitch with the Twin Needle (Stretch twin 4.0/75 is my favorite. OR - if you have Cover Hem as an option on your serger, or the stand-alone Cover Hem machine - then stitch with a cover hem.
 Store in the DARK - do not let it be in the light - this dries it out."