diff --git a/knowledge base/f3.md b/knowledge base/f3.md
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+# Fight Flash Fraud
+
+Tool to test flash cards' capacity and performance.
+
+1. [TL;DR](#tldr)
+1. [Further readings](#further-readings)
+ 1. [Sources](#sources)
+
+## TL;DR
+
+It fills tested devices with pseudorandom data, then checks they return the same data on reading.
+
+
+ Setup
+
+```sh
+brew install 'f3'
+docker pull 'peron/f3'
+port install 'f3'
+```
+
+
+
+
+ Usage
+
+```sh
+# Test drives
+# Destroys stored data
+sudo f3probe --destructive --time-ops '/dev/sdb'
+docker run -it --rm --device '/dev/sdb' 'peron/f3' f3probe --destructive --time-ops '/dev/sdb'
+```
+
+
+
+
+
+## Further readings
+
+- [Codebase]
+
+### Sources
+
+- [Documentation]
+
+
+
+
+
+
+
+[codebase]: https://github.com/AltraMayor/f3
+[documentation]: https://fight-flash-fraud.readthedocs.io/en/stable/
+
+
diff --git a/snippets/check sd cards.sh b/snippets/check sd cards.sh
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+#!/usr/bin/env sh
+
+# Test drives
+# Destroys stored data
+sudo f3probe --destructive --time-ops '/dev/sdb'
+docker run -it --rm --device '/dev/sdb' 'peron/f3' f3probe --destructive --time-ops '/dev/sdb'
diff --git a/snippets/delete partitions.sh b/snippets/delete partitions.sh
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+#!/usr/bin/env sh
+
+# Does *not* ask for confirmation
+sfdisk --delete '/dev/sda'
+
+wipefs -a '/dev/sda'