Keeley pedal without the original box. I don't know the year it was built.

From Keeley's site:

THE GOLD KING!

The El Rey Dorado is your go-to box for that Plexi tone. Yes, there is a wide range of 1960s Plexi Amp Tone in terms of power, which tubes are installed, which speakers and/or cabinet is used, but the El Rey Dorado hits the core tone bullseye! One of the many reference points for the tone was my own JTM 45/100® full stack.  (It’s a dead-on reissue Marshall® did with crazy cool custom-made–vintage-recreation speakers and dual transformers to transfer the load of the 4 EL-84s!)

The El Rey covers a lot of classic British amp tones by featuring two gain modes with the Power Toggle.  With the Power Toggle switch you have control over the compression and harmonics.  Low Power mode is louder, has more girth, and has fewer harmonics for a more old-school tone.  The High Power mode has more compression, more harmonics, and a tighter, more defined tone.  Old-school crunch in Low Power mode, super lead tones in the High Power mode.

Simple as grabbing an open E Chord!

• Volume, Gain, Tone, Power Toggle: Yes
• Keeley Engineered: Yes
• Ripe Tide Gain: Yes