Chamber Flag Safety Block Insert for AR15 / STANAG Mag Lowers

- Orange Color: Clearly show the chamber is empty even from a distance. And says CLEAR near the top of the block, visible from the chamber. - Thick and Sturdy: Printed with high wall count and moderate infill for a sturdy print. - Blocks Bolt and Chamber: The raised portion physically blocks the bolt from going forward. - Locks Into Magwell: Just like an actual magazine, this locks into the firearm and the mag release must be pressed to remove it. - Made in USA: 2200+ products designed and 3D printed in the heart of America in St Louis, Missouri by Hammy3DPrints. MATERIAL: 3D printed using PLA+ filament. WARRANTY: If this item breaks I will make any design adjustments, if needed, and send a replacement for free. Made in USA. Please note that the products may have slight imperfections as 3D Printing is rarely perfect. The exact product you receive may also slightly vary from the product photos as I iterate and improve upon designs based on user feedback.