International standard ISO 7736 defines a standard size for car audio head units and enclosures. The standard was originally established by the German standards body Deutsches Institut für Normung as DIN 75490, and is therefore commonly referred to as the "DIN car radio size". It was adopted as an international standard in 1984.
Head units generally come in either single DIN (180 x 50 mm panel) or double DIN (180 x 100 mm panel) size. The depth is not standardized; as a result, some cars such as the Opel Manta / Ascona have the correct sized front aperture but will accommodate few DIN sized radios other than the original due to the shallow depth; this despite the vehicle being manufactured as late as 1988. The US standard for a DIN radio is 7" x 2" (although the actual 180 mm width converts to something like 7-3/32" so most people use 7-1/8" to allow for clearance) and the Double DIN sized radio is a 7" x 4". Some radios in Japanese Kei cars do not conform to the DIN standard however.
Uniden BCT-15 naked with vehicle dash ISO bracket screw mounts-right.jpeg
Uniden Bearcat BCT-15
Blaupunkt Hamburg MP57 side.jpeg
Blaupunkt Hamburg MP57
ISO 7736 single DIN spacer compartment bay.jpeg
Single DIN spacer pocket
Sony MEX-BT2500 Xplod Bluetooth stereo head unit ISO 7736 installation.jpeg
Rack braces and screw mounts exposed for single DIN installation
Toyota factory head unit and compact disc player with ISO 7736 dashboard bracket screw holes.jpeg
Double DIN combining a single DIN head unit and a single DIN compact disc player
Citizens Band CB Cobra 18 WX ST II without microphone.jpeg
Cobra 18 WX ST II CB mobile radio
Sony MEX-BT2500 Xplod Bluetooth stereo head unit illuminated.jpeg
Sony MEX-BT2500 installed into single DIN
USDM 1991 Legacy LS CD Player.jpg
1.5 DIN OEM stereo with optional DIN sized CD player
Alpine double din head unit in infiniti g35 coupe.jpg
Alpine double DIN head unit
Pioneer FH-P80BT double DIN head unit, installed in a 1995 Volvo 960.
Volvo SC800 double din.JPG
Volvo SC-800 double DIN head unit, installed in a 1995 Volvo 960.
For removing the unit, a pair of U-shaped devices are often used. The devices are inserted in the two pairs of holes, at either end of the stereo fascia, the action releasing the unit from the mounting and providing a pair of handles to pull the unit free. These tools vary from manufacturer to manufacturer. Becker uses a pair of key-shaped removal tools, with one hole each. Often a set of thin screwdrivers will work just as well.
- 19-inch rack
- Connectors for car audio
- ISO 10487, standard for connectors for the head unit to the car's electrical system
- International standard ISO 7736: Road vehicles — Car radio for front installation — Installation space including connections. International Organization for Standardization, 1984.
- Fit a Cobra 18 WX ST II CB radio in-dash in a Toyota Tacoma, with pictures of ISO 7736 bracket modifications
- ISO 7736 document from iso.org cataloge