Got these tubes with several others in a lot that were clearly New Old Stock and appear to have never been installed! All 4 of these tubes feature the same top “Gf8″ code and the bottom codes are Delta8xx / Delta9xx which indicates they are from 1968/69 and manufactured by Philips. In this particular case they were branded for Honeywell. This set tests as NOS+ and is nicely balanced! Also the print is Extremely fragile and will easily rub off, much has already rubbed off, but special care was taken not to rub off any more while testing. The tubes’ test results are displayed in the photos New 12AU7 Spec 100% = 2,2. See the photos for physical / cosmetic condition. Notes Regarding Tube Tests. All tubes are tested on an Amplitrex AT-1000 tester in the automatic Fixed Bias Mode (for the most conservative results). Test Results are for a general reference only, and are not a guarantee of performance, nor a guarantee of how they will test on your tester. No real world (audio) performance measurements are taken.