This product is a re-fabricated neck-seal designed to fit the following models of Sparklets soda syphons:  Original glass straws, as supplied or found on Sparklets Type C, D and "Prana" soda syphons - and their close varients (as pictured)  WITH A TRUMPET SHAPED METAL END.  The outer diameter of the neck seal is 30mm and its thickness is 6mm; the central hole is approximately 14mm in diameter and is intended to be a slightly tight fit on the original metal ends to the tubes.  CAUTION: In general, we recommend that the seals be soaked in hot water prior to use and inserted over the end of your tube whilst still warm, before allowing to cool in place.
 
Care needs to be taken when inserting the old glass tube into the centre of the seal as old glass can be brittle and fracture easily.  It is recommended that stout gloves are worn when doing this.  A water soluble lubricant such as cooking glycerine or even just water is not generally needed.  
 
The seal is fabricated from a food-safe grade of synthetic rubber - hence the blue colour (Either approved for food contact use by one, or more, of the UK Water Research Association, US FDA or EU materials safety schemes).
 
Price includes UK postage; non-UK buyers will need to inquire about postage costs to your country. 
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