Instruction: Given a question and the related document, predict if the question is answerable based on the information provided in the document. Output only yes or no.

Input:
Question: Will they work for a offset backup sight on 45deg rail?
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.
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!
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.
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.
holds zerowell builteasy operation with gloves evenfolds complete from viewdual apertures are perfect sizedawesome accessory
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.
Answer: yes