Instruction: Answer the given question by extracting information from the supporting document.

Input:
Question: What size is the female plug? Will be using to connect 3 CCTV cameras.
Document: The DC Female to 4 Male Power Splitter Cable for CCTV works great. It allowed me to use 1 cable to power 4 cameras.
Not much to say. It's a splitter cable. I used it to power multiple devices off of just one wall wart. The plug is the same size used by most CCTV equipment, and used by lots of other devices as well. Make sure your wall wart is supplies enough current to power all of the devices you intend to power from this splitter.
this is perfect for my car camera. i can add maybe 3 more cameras to my car if i wanted too
Heed the advice of the person that stated his wall plug melted. You cannot take a wire made for 12 volts and multiply it by 4. There are exceptions, if you are using this to power phone's, the wattage is so low there won't be a large draw. Keep in mind, I'm not saying this product cannot handle the power, it is whatever precedes this. Weather it is an adapter or a wire coming from a 12v distribution box.
Arrived very quickly was well packaged and my questions about this product before I bought were answered very quickly. I am using this item to reduce the number of plugs used for my home security system. Having 16 cameras all plugged into a couple of outlets which isn't very safe. After installation about a month ago everything is working great and I don't lose any sleep thinking the house my burn down from the over loaded outlets.
This item is great for installing automobile security systems with more than one power hook up. All you have to do is install one pig tail and plug this adapter in to run up to four different 12v DC electronics.
I only ordered the cable in case we needed to connect something in the near future. I didn't have an immediate need but they arrived on time and the price was reasonable..
it was just like it was supposed to be works well on cameras system I will be getting more of them
perfect, just what i needed to power 4 cameras. the connectors fit tight and i have had no problems with it.
Very good to extend power for your security cameras. You don't have to buy another power supply, just this useful gadget.
Answer: it fits 2.1mm by 5.5mm plugs and I'm using it to power 4 Swann security cameras with no problems