What are the dimensions of the this product? does it come with nuts or screws?

I don't know the exact dimensions off hand (as I have it installed in a rack), but I can tell you it uses two holes on the rail (hence "2U") and it allows wires to fit behind it (16" deep in a 19" closed rack). It comes with high quality mounting hardware (screws and nuts) and feels very solid. I'd buy another one if I needed it even though the one I got had a slightly bent corner as though it had been dropped or banged into something prior to shipping (I just bent it back very easily with some pliers and it has been perfect).

Are these shelves required to rack mount hardware?

No, They simply provide a shelf for components that are not equipped with rack mount ears. (sometimes a more economical alternative to buying mounts for equipment that did not come with them) - keep in mind that they do take up width between the rails and you should measure carefully to insure your component will fit within the approx. 17.18" space. - they can also be mounted "upside down" to allow for full-width components (this does impact the space(s) below though).

will this be able to hold like a 27inch monitor or smaller and a keyboard? plan to put this in my server rack.

This shelf is strong enough for a LED/LCD computer monitor, however the rack width is only 19". A large monitor may not fit due to the width of the rack and height of the sides.

Is this compatible with Blackmagic design Teranex devices?

Compatible ?? It is a shelf, nothing more or less - You simply need to compare the measurements of your device(s) with those of the shelf to verify the fit... I apologize if I missed the point of your question; if so, maybe you could rephrase it to be more specific to what you are trying to find out. (i.e., Will my 17"w X 12"d X 1.75"h device fit?) Cheers

ASIN	B071KW94ZC
Best Sellers Rank	#13 in Computer Racks & Cabinets
Brand	StarTech
Built-In Media	1 1U Fixed Shelf, 4 M6 Cage Nuts, 4 M6 Screws
Color	Single Pack
Compatible Devices	Compatible for Servers, UPS/PDUS, KVM Switches, Network Switches, A/V Equipment
Customer Reviews	4.8 out of 5 stars 2,460 Reviews
Enclosure Material	Alloy Steel
Global Trade Identification Number	00065030867306
Is Assembly Required	No
Item Dimensions D x W x H	9.8"D x 17.3"W x 1.7"H
Item Height	1.7 inches
Item Type Name	Rack Shelf
Item Weight	1.8 Kilograms
Manufacturer	StarTech.com
Mounting Type	Rack Mount
Size	10"
UPC	065030867306
Unit Count	1.0 Count
Warranty Description	Lifetime
Weight Capacity	Maximum weight: 44 Pounds

StarTech.com 1U サーバーラック棚板/19インチ装置ラック&キャビネット用放熱スリット付きカンチレバートレイ/高耐久性スチール/耐荷重20kg/奥行25cm ブラック CABSHELFV1U

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