This is the D'Addario Pedal Tuner Plus.

The Pedal Tuner+ is a high-quality, buffered guitar/bass tuner in a compact format, and slick black aesthetic.  D'Addario's unique vertical display is bright and clear, even under the brightest stage lights and with the 32-bit processor, tuning is quick and precise.

The minimalist look and small size make this a easy squeeze onto any pedalboard, or stand-alone with 9V battery power.  This tuner can be calibrated for reference pitches between 415Hz - 475Hz.  So, yes, you can tune to A=432Hz if you wish... !

• Onboard signal buffer
• 32-bit processor for fast response and accuracy
• Countdown stage timer
• Full-colour vertical display
• Power: 9V battery or 9V DC (300mA) power supply
• Reference pitch: A4 = 440 Hz w/ calibration range: 415 - 475 Hz.

D'Addario says:

"The D’Addario Pedal Tuner Plus boasts the speed and accuracy of our original Pedal Tuner, plus two new features. First, it has a high-quality signal buffer, to maintain your sound across long cable runs and prevent signal loss through your effects chain. Second, it includes a programmable countdown timer to keep track of your set or session time. All of that combines to make a standout multipurpose pedalboard tool — keeping you in tune and on time."