Plastic springs used in small‑volume vial inserts—such as those found in RSA™ and AQ ™ brand glass inserts—are not available for separate purchase. These springs are an integral part of the insert assembly and are supplied only when already attached to the corresponding vial insert. 

This design choice ensures proper alignment, consistent fit, and reliable autosampler performance. When the spring is factory‑assembled, the insert maintains consistent height, stability, and centering inside the vial, which is essential for dependable sampling accuracy. Detaching or replacing springs from inserts can compromise insert geometry, throughput reliability, and instrument precision—hence they are not sold as independent components. 

The springs used in our inserts also contribute to the handling and positioning of very small sample volumes. Their correct compression force and positioning are part of the engineered solution. Providing springs separately could lead to improper installation, which may affect sample recovery, vial seal integrity, or autosampler needle alignment. For these reasons, users should always purchase the complete insert‑plus‑spring assembly when additional springs or replacements are required.