- Prop (Not Real): This item does not do anything functional. It looks good and is for nostalgic / prop / cosplay / etc. purposes only. - Two Stickers: One sticker options doesn't have any red dots. The other has three (3) red dots. The sticker is not intended to be removed after application. You will need to apply it upon arrival. - Picatinny Attachment: The radar / sensor attaches to a Picatinny adapter. The adapter must be able to slide onto the Picatinny rail from the front or rear. On an AR, for example, it's easiest to lock the bolt back, pull the charging handle back, and then slide the Picatinny piece onto the rail. This may require some tapping with a rubber mallet as it is intended to be a tight fit. Once installed, two included bolts and nuts are used to install. - Mount Versions: The standard version slides on from the front or back of the Picatinny rail as pictured. The "Split" version has the portion above the Picatinny rail in two pieces so it can clamp on without sliding the mount on from the front or rear of the rail. The "Extended Split" version is the same as the "Split" version but moves the radar out .5" further to the left to clear larger receivers, such as the Vector 9/45. The "Extended Split Straight" version is the same as the "Extended Split" but has the radar directly below the mount instead of positioned forward - this is useful for the Tavor X95 and perhaps some other bullpups. - Radar Attachment: The hinge of the radar piece is attached to the Picatinny adapter via the included longer bolt with associated nut. Both nuts can use some blue loctite if you would like. - Made in USA: 2200+ products designed and 3D printed in the heart of America in St Louis, Missouri by Hammy3DPrints. MATERIAL: 3D printed using PETG-CF 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 heartbeat sensor style product photos as I iterate and improve upon designs based on user feedback.