3 Pcs. WW1 ARMY BOOT Shoe Felt/Wool DRESS SPATS 2 + Leather Double Strap

Description

I found this set of three items with a WWI Mess Kit (listed separately), and I'm not exactly sure what they are.  Perhaps some WWI buff or collector out there in eBayLand could enlighten me.  How would I tell if they are USA or some foreign pieces?  I believe the pair would be called military dress spats to fit over the top arch of the foot (over the insole of the shoe or boot).  They are a pair.  Made of felt or wool or something like that, and yes, there are some small holes that may have been made by moths.  Leather strap with buckle goes under the shoe or boot.  For buttonholes (vertical) on the outside, with four brown multi-toned buttons.  One button is missing on the left spat.  Horizontal length: 8 inches.  Vertical height:  5 inches.  Length of leather understrap:  6.25 inches.  These are vintage and old and have the moth holes and missing one button but still look great and would be fine for a display.
The second piece has me guessing.  It is leather and looks like it fits over the ankle, but I guess it could be for a horse.  It is sized or tightened or loosened with two sturdy horizontal straps, each secured with a roller buckle.  Each strap has six metal eyelets.  The buckles measure 1.5 inches x 1.25 inches.  Each strap is 3.75 inches long.  On the back of this leather piece you will see a little staining, but some leather conditioner/cleaner should make this quite a handsome piece.
(I just lowered the price July 31, 2020.)
I'll mail all three pieces, carefully cushioned and wrapped, to anywhere in the USA via Priority for .50, which will include tracking and insurance.  I also use the eBay Global Shipping Program.
Please feel free to ask questions or guide me toward different photos.  If you have a minute, check out my other items--lots of vintage (more WWI stuff) and modern stuff, all reasonably priced.  I like to combine items and try to save the Buyer (you!) some shipping money.  Thanks for the interest.