Elecraft 2T-GEN 2-Tone Test Oscillator Signal Generator
VU2ESE | Two Tone Generator
Tempo 601K-G Tone Generator, 2 Tone | RS
IDEAL Tone Generator and Amplifier Probe Kit 33-864 - The Home Depot
TRIPLETT 250-Volt Analog Tone and Probe Specialty Meter in the Test Meters department at Lowes.com
701K-G Tempo | Tempo 701K-G Tone Generator, 2 Tone, 960Hz Tone Frequency | 370-5247 | RS Components
Tone Generator Kit, Wire Tracer Circuit Tester, Tone Tracing Probe Kit, 200EP High Accuracy Cable Tester, Line Finder Toner Inductive Amplifier Variable Tone Generator for Network Cable Collation: Amazon.com: Industrial & Scientific