Wrapping material folded in half lengthways, so when you unroll it, you have two layers of film, ready for sliding the product in between.
Typically used with L-Sealers and made from Polypropylene, it comes in a wide variety of widths.
A sample specification might read: C/F 400/200 750m 25mu.
C/F = centre fold
400/200 = 400mm wide when open, 200mm when folded
750m = length of roll in metres
25mu = 25 microns, the thickness of the film