Below is a list of metal detector manufacturers website links to their home pages and manuals (if available).

The White's Spectra V3i with wireless headphone option.
Purchase the V3i at Kellyco.
White's Metal Detectors
Home Page
Manuals
Fisher Metal Detectors
Home Page
Manuals
Garrett Metal Detectors
Home Page
Manuals
Nokta Metal Detectors
Home Page
Manuals
OKM Metal Detectors
Home Page
Manuals
Teknetics G2+ Metal Detector.
Teknetics Metal Detectors
Home Page
Manuals
Tesoro Metal Detectors
Home Page
Manuals
Treasure Commander
Home Page
Sold exclusively by Kellyco.
XP Metal Detectors
Home Page
Bounty Hunter Platinum Metal Detector.
Bounty Hunter
Home Page
Manuals
First Texas Products, LLC
Cobra Metal Detectors
Home Page
Detector Pro Metal Detectors
Home Page
Minelab Metal Detectors
Home Page
Manuals