https://www.instructables.com/Knex-True-Trigger-Grenade-Launcher-TCEGL29/
K'nex True Trigger Grenade Launcher: TCEGL29 - Instructables
K'nex True Trigger Grenade Launcher: TCEGL29: T: Tactical C: Controlled E: Explosion G: Grenade L: Launcher 29: Uses only 29 peices (Last time I Counted) This...
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