The Brennzunder Eifer 1939 Grenade Fuse consisted of a small, cylindrical metal tube containing match composition with a friction wire passing through it and a delay pellet at the bottom.  The friction wire has a pull lanyard attached and connected to the cap.  


The cap is unscrewed and pulled sharply to initiate the delay.  The fuses were made in four different delay times with those delay times denoted by cap color: Red - 1 second; Blue - 4.5 seconds (standard fuse); Yellow - 7.5 seconds; Grey - 10 seconds.
The BZE 39 Igniting Fuse was used on the Model 39 "Egg" Grenade:


 The M43 "Stick" Grenade:


 
 and the "Hafthohlladong" Anti-Armour Mine:

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