Unbranded Scrulox Drivers

[thefraze_1020]

Recently I found two Scrulox drivers. I have been hunting, trying to find an actual brand name on them, but I am stumped. Both are red-handled and fit (Robertson) screws #8-9-10. They are only marked with the screw size, "Scrulox", "unbreakable handle" and "made in Canada".

I am aware that Scrulox is a trademark of P.L. Robertson Manufacturing Co. Since these have no brand other than Scrulox, are these drivers made by Robertson themselves? If so, any idea the vintage of these?

 

[The Cobbler]

made by or for Robertson, 70's to 80's is my guess as they were very common back then. I have several ( well used) of each yellow #4 , green #5&6 , red #8 , 9, 10, , black #12