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Double Cap

Starting in December 2017, we have begun to supply some of our products using our new "DualSeal" caps for moisture/oxygen sensitive products allowing you to keep them in good condition until the last drop. We will be continuously upgrading many of our current products to our new DualSeal containers.



The DualSeal cap consists of two parts; the outer-cap (blue part) and the inner-cap (colorless-part), both of which can be screwed and unscrewed as normal. For normal everyday use only the outer-cap is used. When the time comes to dispose of the bottle, the inner-cap can be unscrewed.

Over-Cap (blue)

Over-Cap (blue)

The outer-cap (blue) imparts a highly airtight seal providing the reagents ample protection from moisture and air, even after the septum has been pierced many times.
The outer-cap is the portion that is unscrewed during regular use. Do not remove the inner Teflon sheet. This Teflon sheet is key to insuring an airtight seal.


-Do not dispose the inlaid Teflon sheet, keep it as it is during use. This Teflon sheet has a function to enhance airtightness.

Under-Cap (colorless)


The inner-cap (colorless) has wide septum surface for ease of use, and features two layers of rubber and a highly chemically resistant PTFT seal. The inner-cap body is made of polypropylene and is adorned with a screwed joint allowing for easy disposal at a later time. The inner-cap is tightly closed with high torque to ensure product quality and prevent accidental unscrewing.

To remove the inner-cap

  • Use pliers when opening the inner-cap is difficult.
  • To open, firmly clamp the DualSeal bottle. Take extra care to avoid any spillage.
  • The cap and bottle can be separated for disposal. Residual reagent may be residing on the underside on the cap. Please dispose of them cautiously after treating any remaining chemical.

Normal Usage Steps

  • Clamp and secure the reagent bottle before opening.
  • Carefully unscrew the outer-cap only (do not unscrew the inner-cap during normal use).
  • Place the cap near the bottle while in use.
  • Insert an inert gas line [Ar, N2] needle through the Teflon seal.
  • Dispense the amount of reagent required.
  • Purge the headspace with inert gas and remove line.
  • Take the outer-cap lid and screw tightly in place. Note: Do not place tape or Teflon or Teflon tape between the caps, this will significantly reduce seal quality.
  • Unclamp the DualSeal bottle and place in its proper storage location.


 Unscrew Over-Cap (blue) only, (pierce the septum with a syringe needle to withdraw chemical, and then) tightly screw it after use.

-When open in the same way as the normal cap

Under-Cap (colorless) has a screw structure and can be opened by unscrewing it.
In this case, do not remove Over-Cap.