Editing Dead drop (section)

==Methods==
The success of a dead drop depends on the location and method of concealment, ensuring retrieval without the operatives being spotted by the public, law enforcement, or other security forces. Common everyday items and behaviors are used to avoid suspicion.<ref>https://www.fbi.gov/history/famous-cases/hollow-nickel-rudolph-abel</ref> Any hidden location is used.<ref>The Ultimate Spy Book, H. Keith Melton, page 131</ref>

[[File:“Dead” Drop Spike - Flickr - The Central Intelligence Agency.jpg|thumb|right|Dead drop spike<ref>https://www.cia.gov/legacy/museum/artifact/dead-drop-spike/</ref>]]

A ''dead drop spike'' is a [[concealment device]] similar to a [[geocaching#Size classifications|microcache]]. It has been used since the late 1960s to hide money, maps, documents, [[microfilm]], and other items. The spike is resistant to water and [[mildew]] and can be placed in the ground or submerged in a shallow stream for later retrieval. Another example was used by the KGB from a hollowed out [[Bolt (fastener)|industrial bolt]] with reverse threading of the cap to prevent accidental opening.<ref>https://www.buzzfeednews.com/article/copyranter/20-cool-kgb-cold-war-devices</ref><ref>https://www.offgridweb.com/preparation/dead-drops-cold-war-spycraft-for-secure-communications/</ref>

Various signaling methods are employed to indicate that a dead drop has been made. These include [[chalk]] marks on a wall, a piece of [[chewing gum]] on a [[Street light|lamppost]] or a [[newspaper]] placed on a [[Bench (furniture)|park bench]]. In some cases, signals are made from an agent's residence, visible from the outside, such as distinctively coloured towel hung from a balcony or a potted plant positioned on a windowsill.