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

Input:
Question: Does this cable modem come with a coaxial cable or does the coax require a separate purchase?
Document: After a recent and unannounced rate increase to lease my modem i decided to purchase my own and save the $72 a year my ISP wanted to charge. To help protect it i recommend hooking its power to a decent quality surge protector. I even went one step beyond and purchased an in-line surge  for the coax also to catch any spikes that might come in from the utility pole outside. Got it right here on Amazon!TII 212 Broadband Cable TV Lightning Surge Protector
Good cable modem, easy to set up! Plug it in to the power source, plug in the coaxial cable and BAM! A minute or two of letting it configure itself and you're good to go!
Amazon will charge you for shipping to return this so make sure you don't need telephony which would require a more expensive modem that may not be worth saving the monthly rental fee for the cable company's modem.
Pros-1. Easy installation and set upInstalling this modem is very simple. You hook it up to the power and attach the Ethernet cable to your computer and the coaxial cable that comes from your internet provider. Should take no more than 5-10 minutes. You then have to call your internet service provider and they will ask your for the serial number of the device. Once you do provide it they will do the rest for you. In my case it was a breeze.
I brought this modem to replace the one I had from Time Warner Cable after the free lease period ended. I am glad I did that since Time Warner recently announced that it would be raising those lease fees from $2.50 to $3.95. So far, so good. The modem was very easy to install. I just swapped out the old modem and connected the power card, coaxial cable, and ethernet/USB cable.
That's something I say about Apple products, but can say about the SURFboard as well. We plugged it in, called the cable company, in our case Time Warner, to activate it (they need the ID etc.) and within 5 minutes it was working. We've had it for a good month or so and it's never needed re-powering, something the previous Time Warner provided modem did require once a week or so.
I ordered this modem based upon the number of positive reviews. Unfortunately, the one I received didn't work from the start. It powered up, but never received a signal, and I cross-checked this with multiple jacks in my house, and even a new coax cable, while using my perfectly functioning rental unit from Comcast as a control. Still no success. Despite the glowing reviews, it seems I have a dud.
I got this modem about three months ago and have not had any problems. I get download speeds of about 23 Mbps and upload speeds of about 4 Mbps, but I'm pretty sure both of those are limited by my Comcast internet connection and not the modem (I paid for the 15 Mbps connection, so getting 23 is great). I had no problems with installation; I just plugged it in to the coax cable, ran an ethernet cord to my laptop and it worked right off the bat.
I bought this modem because Timewarner Cable began charging $6 a month to rent their modem. This has saved me money longterm and paid for itself in 6 months. In terms of functionality there is a model that has a power switch but this one does not. However the only time I power the modem is if Im resetting it due to issues (which stemmed from my router which has since been replaced) and I don't think the power button on the other model even fully resets it so I don't require one.
This fairly cheap and for the 12Mbps with up to 15Mbps speed from Comcast, this is more than enough to handle it. It comes with everything it says on the packaging, so if you don't have a coaxial cable, you will need to get one separately. We had an old coaxial cable so we had it running very soon.Comcast took a little bit longer. I had to get a installation kit for $10 after I ordered the internet package online. However, there was no need for it.
Answer: No, it doesn't come with coax.