*Of N51A borosilicate glass with slight shoulder
*Hollow polyethylene stoppers have knurled flange, open bottom and tapered plug portion that fits tightly into tooled neck

Tooled neck OPTICLEAR vials are fabricated from N-51A borosilicate glass. Necks are tooled for an accurate fit with polyethylene closures. Vials and closures are supplied in both the pack and case quantities. The 1 dram size is supplied with open bottom closures.