Momof3E's they have precuts that are called twice the charm. they aren't charm packs, there is depending on the collection, there is any where from 14 to 20 strips that measure 5 1/2" wide by roughly 20 1/2" - 22" long....here is an example of a twice the charm roll.
http://www.fatquartershop.com/store/...79&Parent_Ids=
depending on the collection, there is anywhere from 14 strips all the way up to 32 strips.
The collection I used was a Jinny Beyer collection called Necessary Neutrals and it only had 14 strips in each bundle so I happened to have 4 bundles and the pattern for the smaller quilt 68x81inches called for 21 strips for the windows so I had to open up 1 full one and 7 strips from another bundle. Hope this helps.
One can find this pattern called Shadowbox by Mountainpeek Creations designed by Kari Nichols
http://mountainpeekcreations.com/