I bought this item to replace a 4AB3C1B Accutronics reverb tank in my Fender Twin Amp (ProTube series). The Accutronics tank was working, but it wasn't producing as much reverb as it should have been and had begun to feed back if I set the reverb at 7 or higher.This MOD tank sounds far better than the Accutronics tank I replaced. It sounds a lot like the old Accutronics reverb tanks that were made before the company started producing junk. It produces a much smoother sound than current Accutronics tanks.This tank has a far more reverb at any given setting when compared to a current Accurtronics tank, so I find that setting it to 4 is about like setting the old tank to 7. If you set this tank at 7, it sounds like a good working Accutronics tank maxed out. If you max out this tank, it produces more reverb than you probably want.Construction of this item is a little better than that of the tank I replaced. It is the same size as the same model Accutronics tank it. There are 4 clear rubbery feet/mounts that isolate the tank from the amp. Also, when you move this tank around, the springs don't slap the metal quite as easily as with the stock tank.The item was packed in bubble wrap with foam blocks above and below the springs to keep it from slapping around in shipping.I highly suggest using this reverb tank.

Finally, a reverb tank that's built like, uh, a tank. I dropped it after playing through it the first time and thought it was done for--smacked the concrete hard enough to bend one corner of the chassis back at a 90-degree angle. Turns out it was fine. Definitely a sign of high quality parts built into a sturdy enclosure. In terms of sound, it works great with my Fender Twin Reverb. Mine is early silverface, but from what I've heard this model fits all Twin Reverbs, even the reissues. The effect is pretty lush and deep when dimed, but it stays surfy. EQ things right and you can get a pretty perfect, washed out trail behind your playing without losing your notes.

High-quality unit. Very cavernous-sounding - long reverb tails. Not exactly the sound I'm after, but if that's what you're looking for, here it is.

I'm happy with this product.I had trouble with the old reverb tank off and on since I bought the amp new.I've had this in for over a month and it has been hanging in like a trooper.It sounds very much like the part i replaced only more dependable.Good job

After two accutronics tanks failed on me fairly quickly I decided to give this a try. Reverb sounds great in my Pro Reverb and it looks like the design is an improvement and less likely to fail. So far, so good.

The Mod tanks, in my humble opinion, sound very good. I aint quite sure if they're better than the USA accutronics, but they're damn close.The reverb is deep and wet, and they really do sound like the real tanks from the 60s.Whatever they did they did it well.

These tanks are absolutely great. A huge improvement over all current production tanks. I swapped my stock Accutronics tank in my Fender Reverb Unit reissue for the MOD tank and the difference was staggering. Major increase in "drip" and much smoother sound without the piercing brightness of the Accutronics tank. I can't say enough good things about these tanks, highly recommended.