16 gauge retainer. Glass septum retainers can be used to conceal piercings. This glass septum retainer features a 1/4" between the posts and has an 8mm length. The retainer is flipped up into the nostrils following insertion into the septum piercing.. Specifications: 16 Gauge (1.2mm), 8mm Length, Borosilicate (Pyrex) Glass, Made in the USA. Septum Retainer 16 Gauge Clear Borosilicate Glass