Item # Description
  403-638X 300µL Glass Conical Limited Volume Insert, Precision-Formed Mandrel Interior, No Spring, 100 per case View Product
  403-638XZ 300µL Glass Conical Limited Volume Insert, Precision-Formed Mandrel Interior, No Spring, Silanized, 100 per case
  403BS-638X 300µL Glass Conical Limited Volume Insert, Precision-Formed Mandrel Interior, w/Bottom Spring, 100 per case Product ID not specified.
  403BS-638XZ 300µL Glass Conical Limited Volume Insert, Precision-Formed Mandrel Interior, w/Bottom Spring, Silanized, 100 per case
  403TS-638 300µL Glass Conical Limited Volume Insert, Precision-Formed Mandrel Interior, w/Patented Top Spring™, 100 per case View Product

Inserts are available preassembled with a polymer bottom spring or patented Top Spring™. The polymer spring acts as a shock absorber that protects against breakage if the needle bottoms out. The conical design permits complete sample removal.