Tuner

Round tuning fork. A=440Hz

K&M tuning fork A=440Hz, model 168/2. Rectangular steel

Round tuning fork. A=442Hz

A classic pitch pipe, that allows you to play a specific tone within the chromatic range. Often used by Barber Shop Quartets. 

Chromatic Pitch Pipe P-13E

Tuner and metronome - two in one!

KORG TM60 Combo tuner and metronome

Combined tuner and metronome.
Metronome from 30 - 252 bpm.
Calibration range  A4=410Hz-480Hz

Korg TM-70T Combo Tuner Metronome