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: Can this be used without the screw-in mounting brackets?
Document: It was too long for some door frames really had to be extended for others. I have used it a couple of times and it feels like it slips a little (probably because I am not using the mounting brackets because they are rather large).
One of the best things about this fantastic pull-up bar is that it is adjustable and can fit into different doorways (up to 36" I think). While living at home I had it screwed into my bedroom doorway with the screw in mounting brackets that came with it. However, I have recently moved out to university and have been able to bring this with me.
Didn't come with the hardware, was poorly packaged, and arrived late. It's not bad, not great. I'm able to use it without mounting brackets (I weigh just shy of 110 lbs though, so can't speak to it's ability to hold a bigger person). It does the job but I don't love it.
The rubber ends of the bar do a great job of keeping it in place once you've tightened it to the point that the center of the bar will no longer move.I haven't had this product for very long, and I am only 135 lb, but I feel safe using it when it is properly installed. I am currently living in a location where I can't screw the mounting brackets into the wall so until then I'll use caution, but I don't see there being any issues.
I got this for my daughter, age 6 -to play/practice simple gymnastics on. Would have been fine if not for the giant screw right in the middle of the bar. I know it's not intended for this purpose but the screw isn't shown i the picture so I thought it'd be okay. It would be great for pull-ups and is easily installed and moved.. Even without the brackets it's secure. Shipping was fast. It arrived 3 days after i ordered it.
All of the hardware was present.Cons:  There is a screw right in the middle of the bar. It's not a problem for me as I use the bar solely for pull-ups, but it may be for others. **A couple of caveats... First, I recommend using this bar with the mounting hardware.
Bought this for my son and he loves it. Super easy to install (used the brackets for extra support). Works great and no issues!
It's a great bar, and I really like it, but please take the time to install the mounting brackets instead of trying to rely on the rubber ends (like I did initially).Let me start out by saying that I only weight 120lbs.When I first put it up in my doorway, it worked fine for a few seconds, then started to slip. I moved it back into position, and tightened it harder this time.
I bought it for my 2 years old daughter, that likes to hang on furniture. She loves it. As other reviewer said you don't have to screw it and it takes a second to put it in and take it out. Has rubber on both ends that helps to attach it tight. Holds adult weight as well without screws (I am - 130 Lb, my husband - 190 Lb).
Used this without drilling into the frame, but it pushed the frame wide (causing a nail head to poke through) and left very noticeable black marks on the door frame from the rubber ends. Not sure what options are available without enough clearance for a pull-up bar that hangs on top of the frame.
Answer: yes