Yeah, brass holders work ok, I use them here when running lamps in our laboratory retort stands. They obviously need to be earthed/grounded, though.

You should have asked me, I've got loads of them, they're dirt cheap on UK eBay.

Rommie, so are standard UK lamp holders the same as BY22d used on SOX?
That changes everything for me. I can get BY22d overhere in Europe but there's hardly any choice and they're expensive.
If they're the same I just go order some nice looking ones from ebay UK (too bad I didn't know this before Brexit happened)

It depends, do you want the ceramic type as used in most fixtures, or the pendant type as on this little piece of home made stuff, and the same as most houses here have for their room lights..?

The former is best if you're thinking of making some sort of fixture, but the pendant type is better if you just want a flexible cord for attaching to a ballast in a temporary setup.

FYI the designation BY22d refers to the lamp cap rather than the socket, normal lampholders are B22d, the Y refers to the piece of insulating material between the contacts of the cap which is there to help minimise flashover between the terminals due to the higher than normal open circuit/ignition voltage. Both types of lampholder are fine for normal use, the ceramic type is probably better, but if you need a flexible cord type lampholder then I'd recommend a brass one.

I can send you a ceramic one or a plastic pendant one, but I don't have any spare brass ones at the moment. Let me know.

The brass B22 holders are good if you want to be creative and add more original design while making SOX low pressure sodium fixtures except that SOX low pressure sodium lamps MUST NEVER be operated base down or base up (if the lamps are 90w and higher).

For example, I used brass B22 lampholders to create a SOX table lamp that uses 2 horizontally mounted 18w SOX low pressure sodium lamps.

It depends, do you want the ceramic type as used in most fixtures, or the pendant type as on this little piece of home made stuff, and the same as most houses here have for their room lights..?

The former is best if you're thinking of making some sort of fixture, but the pendant type is better if you just want a flexible cord for attaching to a ballast in a temporary setup.

FYI the designation BY22d refers to the lamp cap rather than the socket, normal lampholders are B22d, the Y refers to the piece of insulating material between the contacts of the cap which is there to help minimise flashover between the terminals due to the higher than normal open circuit/ignition voltage. Both types of lampholder are fine for normal use, the ceramic type is probably better, but if you need a flexible cord type lampholder then I'd recommend a brass one.

I can send you a ceramic one or a plastic pendant one, but I don't have any spare brass ones at the moment. Let me know.

Thanks so much for clearing that up Rommie and thanks for the generous offer.
I've been looking on eBay and Amazon UK and there's a wide variety available so I'll just place an order there. And now that I know what to look for, even AliExpress has them listed. I love the brass versions.

The brass B22 holders are good if you want to be creative and add more original design while making SOX low pressure sodium fixtures except that SOX low pressure sodium lamps MUST NEVER be operated base down or base up (if the lamps are 90w and higher).
For example, I used brass B22 lampholders to create a SOX table lamp that uses 2 horizontally mounted 18w SOX low pressure sodium lamps.

Thanks for the warning. Yes, I also tell people to put the socket on top if they want to use them vertically. There are a few videos on Youtube where people have mounted them the wrong way round too.

One thing you will need to remember if you use a brass lamp holder is that it will need to be earthed / grounded. 

One other question: where can I get a socket for 55W SOX?

Here you go - just got my box of 10, less than a dollar each including postage. Good quality.

https://www.ebay.com/itm/233156388009

Expect about a month for shipping to US with standard postage though.

I'm wondering what florescent ballast works best to power a 55W SOX lamp. I'd really like to see my lamp lit.

Now that I finally got my bayonet sockets, I’m ready for a test of the Fulham WH8 on one of my 55w SOX lamps. According to the ballast spec, that will drive three 0.580 amp TUV25W G25T8 bulbs with 2 red wires each. I asked Fulham tech support if that would also work with just two of those 25w fluorescent lamps on the WH8, and they said that would overdrive them about 10%. Assuming a total load of 55w from the SOX lamp would be similar, I’m going to try 2 reds on that and anxiously watch the run up wattage with a finger or two on the power strip shutoff. Stay tuned here.

Better yet, let me know right away if anyone has already sustained major fire damage with this test! (I’ll send them one of of my lamps & some more good ideas.)

@ clarkrs - That's the seller I generally get mine from.

Here you go - just got my box of 10, less than a dollar each including postage. Good quality.
https://www.ebay.com/itm/233156388009

How?
They're asking $5.40 per piece...

They usually have multiple listings for different quantities.

Sorry - wrong link.

Same seller but I picked the “10x” offer
https://www.ebay.com/itm/363438614957

Much better deal!

Yeah, that's a better price..? I've bought several lots from them.

Sorry - wrong link.
Same seller but I picked the “10x” offer
https://www.ebay.com/itm/363438614957
Much better deal!

Thanks!