Stock STRATA vials and caps are sold in sets with equal parts per case, and have an ongoing 5+1 special. STRATA vials offer flexibility and are an excellent value compared to other U.S. made reversible vials. Three vial colors are available, and custom caps are our specialty. Custom Cap users purchase caps in bulk, and STRATA NC – No Cap – Vials as needed. STRATA is certified by Script Pro.