If you never have to travel and transport your strobes via airlines, no need to read further. Because I travel for about 45% of my work via airline I am constantly placing my strobes and modifiers into checked luggage. All of that gear is subject to brutal, errr, TSA inspection. They open my luggage around 95% of the time to ‘see’ what’s in those mysterious cases. I use a SKB 2SKB-4814W Deluxe ATA Golf Travel Case to transport my Parabolix, Elinchrom, etc modifiers. For my strobes I carry them in a Pelican 1560 Case With Padded Dividers. I remove the batteries from the strobes along with the bulbs. I remove the batteries to prevent having a TSA agent accidentally turn on one of the units. In the past I didn’t remove the bulbs, but on one trip I discovered the agent (who conveniently neglected to leave an agent ID tag in the case) had broken a bulb. I always pack an additional strobe just as a back up, so it wasn’t a big deal.
Since that time I always remove the bulbs and carry them in my camera carry on bag. I searched long and hard for cases that would safely hold the bulbs. The only case I could find were for the AD200 bulbs and made by Cheetahstand. Alas Edward no longer carries any of the Godox line of strobes, or any of the bulbs or the protectors. Glad I got a bunch before he discontinued carrying them. But fret not, you can make your own out of some PVC pipe.
So here is my solution for AD600 bulbs:






AD200 bulb protector



Even though Cheetahstand doesn’t offer these any longer, you can easily make one out of some PVC tubing with end caps. I don’t know what diameter, but you can measure the bulb and determine that for yourself.