46.5" or 48" VHO?

I'm about to finish an order at BRS and need to replace the bulbs that came in my used canopy set up.

I found the exact bulbs, because I do like them. They're UV VHO t12 Super Actinics. But they offer them in two sizes: 46.5" and 48"

How do I know which ones I need?

 

What fixture are you running?

 

Its inside a canopy that was built by the previous owner.





He had groves cut that the endcaps fit in when I close the lid. I just don't know where to measure from. If I go from where the groves are cut it's a little over 48" from side to side.

 

Just measure bulb tip to tip....what does it read?

 

that's what I wasn't sure of, if they were measured bulb tip to tip, or end cap to end cap. I'll get it out and measure just the bulb in the morning.

 

If I measure it from endcap to endcap like pictured, it reads 47 1/4"



If I measure just the white part of the bulb, it's 46 1/2"




So I'm guessing 46.5 is what I need? Can anyone confirm this before I order

 

48" you will need

 

I need 48's then?! That would be good news since they're out of stock of the 46.5 lol


It is just about 48" if I go from prong to prong on the ends.