Here is a link to info about the pHep 4 meter. It's a good one for wine testing. I belive the Winemakers Toy Store sells this one. At this link, you can view the manual by going to the download tab. It also will detail other products you will need such as the 4.0 and 7.0 calibrators. You should also get an electrode cleaning solution.
I really like it. I like being able to get the probe into the top of a carboy for a measurement w/o drawing a sample to test.
I calibrate, rinse and run down a line of carboys very quickly with a rinse in between one. Less than 5 min to test/record pH for as many as 12 or more wines (after calibration, which takes a minute or two).
I have distilled water in a jug with the carboys and put the temp probe in that.