The cheapest and most effective safe light.
Many people find themselves disappointed to find that the have subtle fogging caused by too bright a safe light or defective filters etc.
When one prints with a safe light and views the developing print one is blessed with the magic of seeing the print develop. I am sure that most everyone that does B&W printing can remember how special it was to see a print come up in the developer. It happened to me over 40 years ago.
it may seem strange that, given the foregoing that I use the following practice. I use no safe light whatsoever. I process my prints entirely in the dark for the full amount of time at the chosen temperture. What are the benefits from doing this? No safe light fog. No pulling of a print that is developing too fast. A firm basis on which to judge any exposure or contrast changes by having a controlled process and viewing a fully developed print.
I view the wet print under illumination that is equal to the conditions to which I expect it will be displayed and viewed. This is very easily accomplished by having a light over your print holding tray that is connected to a lamp dimmer...about a $10.00 expense. The lamp is set after taking a reading of the anticipated display area with a light meter and adjusting the lamp to match.