The self-illuminated Meprolight FUBS are known for their durability and ease of use. Constructed of fiberglass reinforced high grade polymer and metal, the tough, tritium enhanced, secondary sights are designed to lay flat against the picatinny rail to maintain a low profile out of the way until needed. The rearward operating spring allows you to quickly flip them up into place when needed.#html-body [data-pb-style="62DF8289A27AC"]{justify-content: flex-start; display: flex; flex-direction: column; background-position: left top; background-size: cover; background-repeat: no-repeat; background-attachment: scroll; border-style: none; border-width: 1px; border-radius: 0px; margin: 0px 0px 10px; padding: 10px;}#html-body [data-pb-style="62DF8289A27B9"]{border-style: none; border-width: 1px; border-radius: 0px; margin: 0px; padding: 0px;}