Dating fender twin
The code follows the format: = a number from 1 - 52 indicating the week of manufacture.
Remember, your amp is newer than the newest component.
In a BF Vibrolux Reverbs you could have either Jensen, CTS or Oxford, the BF Super Reverbs had Jensen, CTS, Oxford or sometimes JBL, the BF Pro Reverb had Jensen, Oxford or Utah, ++.
In the silverface era Eminence, Oxford, Utah and Rola were more often used and Jensen was phased out.
These are marked with EIA code “606” which is the company number for Schumacher.