Mobilistics model WH-S16A approximately 1-3/16" wide x 1/2" high with offset tab on bottom.

Plugs into Sony Radio 16 pin receptacle on back of unit. 8" color coded leads with bear ends. All wiring has Electronic Industries Association: standard color codes. Each wire is stamped with wiring location for easy installation. Customer 800 HelpLine. Full 1 year warranty.
Check our ebay store for the replacement plugs for SONY  9 pin, and 18 pin, radio plugs.
FITS ONLY THESE MODELS:
CDX-GT65UIW, CDX-66UPW, MEX-BT38W, MEX-BT39UW

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