The 
Saigo Defense Kamikaze XS Black Grenade
 is an impact-activated, reusable airsoft blank firing device that uses 9mm blank rounds to simulate an explosion. It is constructed from durable aluminum and steel and features a simple "bobble-head" firing mechanism. 
 
 
Features and Specifications
Activation: Impact-activated detonation.
Ammunition: Fires 9mm blank cartridges (a specific adapter is also available to use 6mm BBs with it, sold separately).
Materials: Constructed from a combination of stainless steel and aircraft-grade aluminum for durability.
Design: Utilizes a simple and effective "bobble head" design with a unique ring-pull system safety collar.
Dimensions: Approximately 100mm (height) x 34mm (width).
Weight: Approximately 334g.
Color: The black version has a self-adhesive vinyl sticker to indicate the color.