There has been a discussion for some time about the correct bulb to fit to a Valoy 2 enlarger. An excellent illustration appears on one commercial website which has been on display for some time.
This refers in particular to Osram products (beloved by the factory) I was at a loss to know what I should fit to be correct, although I had used a Valoy for years with no complaints and any old 75 watt enlarger bulb that came to hand. I have just checked my small stock of bulbs and find that the 75 watt bulbs of modern issue in bright glossy boxes all measure 4.13 inches long which is even shorter than the 'short' Osram product, but,, moreover, also shorter than early Phillips bulbs in distinctly 1950's packs. I would assume that I have bulbs small enough to give optimum coverage in a Valoy 2 -if I notice !
As ever, comments on this tenuous point are welcome at the email address above as the 'comment' facility seems to have ceased to function.