The #HB-115 is the same blade used in the "Steinbit". It is just over 6", thin (just .087" at the base) and fairly flexible,
These are quite popular for fish of all sizes as it is small enough to do just about anything but just stiff enough to handle any sized fish.
Second Picture shows the comparison between the Steinbit and the Hellefisk
Link to the Butt End that Helle uses for this blade
End Nut #5
