A third, relatively important, development : For the "1951 Model" the knife’s length decreases from 100mm to 93mm, it becomes rust resistant  (stainless steel), the blade is once again curved as in the 1890 model, the screwdriver has a notch for stripping electric cables and the rivet shaft, holding both the tin opener and the awl, has a 2mm hole so the knife can be used as plumb-bob (when using the FASS 57 rifle as a grenade launcher). However, in 1954 a 6.2mm diameter rosette reinforced the drilled rivet. From 1957 to 1964 the soldiers’ knives were manufactured with sides made of Grilon (commercial name for a family of thermoplastics), but this production has remained an exclusivity for the company Wenger.
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