Advanced PTFE Stopper Now Available

Hi everyone,

The Fireflyers are here to let you know about our latest product.  The large photo might have given it away as well as the title of this article so I'm sure you won't be surprised when I tell you that the new product is a PTFE stopper.  

But what makes this new stopper so unique?  I'm glad you asked that!

The FireflySci Advanced PTFE stopper is made from a special process that enables the relatively hard ptfe material to be more flexible and soft.  What this means is that these new stoppers conform to every curve of the cuvette stopper hole.  Even if the hole is drilled uneven, distorted, oval shaped, etc. this new stopper will give you an air tight seal every time.

Why would I need one of these stoppers?

PTFE/Silcon Septa

PTFE/Silcon Septa

Many researchers need to have the tightest seal for their experiments.  In the past the best sealing cuvette you could buy was a screw cap cuvette with a septa seal.  Being able to tighten down that screw cap meant that you could rest at ease that your sample was hermetically sealed.

The problem with this method was that the septas would need to be changed after each use.  Since the septa is a combination of PTFE and silicon, the PTFE layer would become "indented" when the cap was screwed down.  If you have a screw cap cuvette you know exactly what I mean.  This indentation makes the septa unusable since it won't give you a hermetic seal again.  Septas can be pricey, ours go for $3 a septa, but wouldn't it be nice if you didn't have to worry about needing additional septas?  Also, if you're like me, you loose these things all the time because they're so small.

Here is where our new Advanced Stopper comes in.  You can get that same hermetic seal, with using one stopper time and time again.  What I really love about this stopper is that it only costs $15.  And what's better is if you already own our stoppered cuvettes you can easily upgrade your stoppers and benefit for the enhanced seal.

One area that would instantly love to get some of these stoppers is for those small labs that make their own calibration standards.  Simply permanently glue the stopper in place and you'll have a safe, hermetically sealed calibration standard.

These stoppers are in stock and can be purchased from the accessories product page or to make things easier just click this link.

If you have any questions about the awesomeness of these stoppers please feel free to contact us at

Here's to your success!

The FireflySci Team