Instruction: Output yes if the supporting document can answer the given question. Otherwise, output no.

Input:
Question: hello, what is the rear aperture size ?
Document: Purchased these sights for my husband's birthday due to the other positive feedback posted about this product. I received the item much sooner than expected and even received an extra rear sight. I was unsure of what his reaction would be and was pleasantly surprised when he said &#34;these will work perfect.&#34; He mounted them on his gun that night and we shot it with these sights on the following weekend.
received in a timely manner. the front sight, i like it. the rear sight moves from left to right and from front to back. not happy at all with the rear sight. i will be sending the rear back for exchange and i'm  having to pay freight back charges. if a product is defective i don't see why the purchaser should pay freight back for exchange. maybe i will  get a good one this time. i wish the selling company could see this post.
holds zerowell builteasy operation with gloves evenfolds complete from viewdual apertures are perfect sizedawesome accessory
I was looking for backup sights for my AR that wouldn't break the bank. I came across a couple sets, rather than buying themone piece at a time.I picked these particular pair by the other reviews. when I received them i was pleased with the weight of themand they were metal rather than a lighter material.put them on look great the ball holds great when flipped up or down.like themvery much.
I received the items quick and at a fair price for them and from what I have seen from them they will hold up better than the polymer flip up sights I have used.
Graet back up sights and it won't break the bank. They're heavy, and kinda of &#34;clunky&#34;, but they work and i'm keeping them!
Answer: yes