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Klean Kanteen Classic Steel Loop Cap

A replacement cap that gives a Klean Kanteen Classic a steel drink side.

Source-reviewed $ · indicative price band Reviewed

Price & availability: $14.95 listed by Klean Kanteen on September 26, 2026.

Read the full guide: Do glass bottles have more microplastics than plastic ones? →

Why consider it

  • The manufacturer describes an 18/8 stainless steel cap, threads included, that creates an all-stainless interior.
  • Listed as leakproof and dishwasher safe.
  • Replacement o-rings are sold in the Classic Cap Maintenance Kit, which lists the Steel Loop Cap as compatible.

Practical tradeoffs

  • Fits only Classic narrow-mouth bottles with internal threads.
  • Not intended for hot beverages, according to the manufacturer.
  • Not polymer-free: a Klean Kanteen staff answer on the cap maintenance kit page, not the product page for this cap, says its cap gaskets are food-grade silicone.
  • It changes only the cap; the bottle body and any exterior finish stay the same.

Our assessment

This is a manufacturer-document review, not a use test. The cap only makes sense if you already own a Klean Kanteen Classic, the narrow-mouth line with internal threads.

The manufacturer describes the cap as 18/8 stainless steel, threads included, and its cap gaskets as food-grade silicone. That changes what touches the drink. The cap has not been measured for particle release, by us or by anyone we found.

If your current cap is intact and you are comfortable with it, keeping it is a reasonable choice.

Start with a decision, not a purchase.

Write down what your current item fails to do. If it still suits you, a shopping list can wait.

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These cards link to our research notes. Any enabled affiliate shopping link on a reviewed page is labelled and may earn us a commission. Disclosure

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