Gary Holt

http://youtu.be/0d2_5FYtcFc?t=78 (above the MXR noise gate rack)

Presonus EQ3B Equalizer shown at 58 seconds into the vid. he used this on Exhibit :B album.

The TC Electronic G-Major II can be seen 1:26 into the video.

The Radial JD7 can be seen as of 1:28.

From the interview with Premier Guitar:

What effects did you use for Blood In, Blood Out? Holt: I use a ton of different pedals. I love stompboxes—they’re like crack to me! I have pedals from Maxon, Dunlop, HomeBrew Electronics, Pigtronix. I use a lot of the Maxon Tube Screamer-type pedals. They made the original ones, so they have ones that are exactly like the original, sought-after ones, and they also have updated versions.

I also love the Boss Octaver. I’ve never been without one my whole life. Dunlop makes a bass octave pedal, which sounds probably even a little better and has a smaller footprint, which I also like. And I use a Voodoo Lab Ground Control. With Slayer, I’ve been using the Dunlop Jerry Cantrell wah. Kerry [King] uses the Zakk Wylde wah, so I wanted something to differentiate our wah sounds.

http://youtu.be/0d2_5FYtcFc?t=79 (check around the 1:19 timeframe) The original product : http://www.jimdunlop.com/product/m235-7-10137-02420-5.do (custom shop is part of the name, not a special order)

Used in his Slayer rig.

Garys Guitar Techs talk about his Slayer Cab setup for live shows starting at 8:06 and Mention using a Radial JDX as a DI.

Mentioned by his Slayer guitar Tech at 0:15 in this gear run.

Mentioned and shown in this Gear Run at 0:44

Mentioned at 0:50 in this Gear Run of his Slayer Rig.

In the studio footage for the last Slayer studio album, you can see the Distressor working in the background while Gary is tracking at 1:04