The product on offer is the GLK001003YGZ by Night Fision. This premier company utilizes an advanced injection molded process, combined with military-grade polymer and durable tritium outlines. The result is an adaptable product that provides superior visibility during the daytime.Aside from the tritium vials, which are imported from Switzerland, all other components of Night Fision products are manufactured and assembled right here in the USA. This guarantees you high quality and trust in what you\'re purchasing.The night sight set is unique, featuring a square front green tritium with a yellow outline and a square rear green tritium. It\'s designed to perfectly fit Glock models ranging from 17/17L/19/22/23/24/25/26/27/28/31/32/33/34/35/37/38/39.