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bob213's avatar
bob213
Explorer
Sep 02, 2020

TST 507 cap o rings

I thought I had more o rings when I replaced my batteries but I don't. Does anyone know the size I need to replace them. Hard to spend $16.50 with shipping just to get the o rings.
I thought I had at least one so I could take it to the hardware store to match up. Any help would be appreciated.

Someone told me 11mmx1mm. Can anyone verify that?
  • Whiskey River wrote:
    Yes... #30 O-Ring They are 7/8"OD x 3/4"ID x 1/16" Cheap at Lowes or Home Depot for a box of 8 or 10.....


    Those seem to be about the size of ones I used when I had flo thru. The regular caps I have now are less than 1/2 inch od.
    Thank you anyways.
    I think I will try the 11mmx1mm.
  • Yes... #30 O-Ring They are 7/8"OD x 3/4"ID x 1/16" Cheap at Lowes or Home Depot for a box of 8 or 10.....
  • Visit harbor freight if you have one. I bought a box of O rings, all sizes, really cheap. Sure there will be some in it that will fit.
  • I found some at ACE Hdw that works just fine. They are a little larger than the OEM but they seal the cover just fine.

    TST quoted me a ridiculous price so I found these that do the job.
  • My measurements came out at .9mm X 11mm o.d.. I don't think that the o.d. is that critical as they get stretched a lot.
  • I’ve heard #30 O-rings work. Can’t vouch for it, but got some at HD and they seem reasonable.
  • Call TST. They may send you some. Good customer service.

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