Instruction: Extract information from the supporting document to answer the given question.

Input:
Question: How heavy can each monitor be?
Document: This is a sturdy, heavy, well built dual monitor stand. I'm using it with a pair of Lenovo 22.5" panels and not only does it work great - it looks great!
I love this stand and I expected it to be a little large and heavy, but what I got really took the cake. I got this because my desk is tempered glass and I couldn't drill through it or clamp anything on it, like you have to do with other monitor stands, without doing damage.
Really sturdy and heavy. Holds large monitors too. Had others in mind but glad I got this one. Dual mount capable in desk with cable management holes in them. I would only replace if I decide to go with a triple monitor set up
This stand works well, heavy duty base that allows a lot of flexibility in monitor positioning. We use it with two 24&#34; lcd monitors with not problems. Our user likes to have the monitor elevated higher than a normal screen mount allows, so this works well for him.
Perhaps this product has been made worse since other people reviewed it, or others simply don't mind very downward-tilting monitors, which I find hard to believe.Do NOT buy this product unless you don't care that your monitors tilt down or that you have to put a heavy object behind each monitor to force it upright.
I have two monitors mounted to this stand, on a Asus 22 Inch monitor that has no issues, the second is a Samsung 2333HD that is two heavy for this stand. the slightest touch will cause the Samsung to lean forward by about 15 degrees. I have looked for a method to tighten the tension on the pivot, but I can not find one, either on the pivot, or online.
Other than that, everything works fine! The base is suitably heavy without being a lead brick, and even without the clamp arrangement it feels pretty sturdy. I'm loving the extra tools they included for the clamp setup, but if they were going to go that far, why not include a cheap screwdriver?EDIT: I just looked up the specs on the Dell monitor, my problem child, and it weighs about 7.5lbs without its stand.
First of all to those whom are having problems with heavy monitors making the monitors point down, take a look at the last page of the manual, you'll need to pop the caps off the rear of each monitor bracket and tighten the nut with the included wrench. I did that and now have no problems with that end.I do wish however that this stand had an individual height adjust. I have 2 similar  monitors, but when they are mounted to the stand one sits considerably higher than the other.
Nice and heavy base, that's necessary to hold my two semi-heavy 24&#34; Asus monitors. While there's already lots of positive reviews about this product, I'll share some of my challenges/notes w/ my two 24&#34; monitors:1. While installing the stand was trivia, do note that the stand will not balance when you first install the first monitor while it's stretched outwards as shown in the picture. I had to push onto the legs to keep it balanced.
The stand is very heavy duty and solid. But when I put my two monitors on (Vesa) they tilted down and won't stay facing forward.
Answer: My Samsung SyncMaster 2333HD is on the upper edge of how heavy a monitor can be, the stand can barely keep it from twisting forward.  Shipping weight on the monitor is 17.9 pounds, most newer monitors should weigh less.