The small, delicate veins of many companion pets pose venous blood collection challenges. Pre-evacuated tubes can easily collapse fragile veins, while a gentler collection with a syringe requires a transfer and can result in insufficient sample quality. The innovative S-Monovette multi-sampling, closed blood collection system provides a choice of collection technique to accommodate varying vein conditions. • Serum- S-Monovettes contain beads coated with a clotting activator (silicate). As a rule, this clotting additive enables the blood to clot within 20 to 30 minutes and the sample can be centrifuged. The beads form a layer between the blood clot and serum during centrifugation.