I came across fluorescent light protectors for T38 (T-12) bulbs. They come in 4 ft or 8 ft, and are made of clear plastic, but very durable.
T-12 protectors can be found at Home Depot, but i haven't checked the inside diameter of those. I purchased 3 tubes of 8 ft length for $2.00 per tube on clearance from a local home hardware store (not Home Depot).
The inside tube diameter is 1.6" or approx 42mm and 39 mm chips fit perfectly inside, with a bit of wiggle room.
I found caps that fit inside the tube which are 40mm in diameter on
eBay (Round Plastic Black/White Blanking End Caps Tube Pipe Inserts Plug Bung 6mm~50mm)
Here is a pic of the tube with a bunch of extra chips in it. The tube can be cut to any desired length.
It's an option for anyone wanting their starting stacks to be in tubes, for ease of counting on rebuys, etc.
I use my tubes for the rebuys, as my starting stacks are already at the seats.
I also use the tubes to store extra chips.
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