The SK40 is equipped with a reinforced release mechanism, stainless steel trigger and double hole head (size 90). size 80 and 100 single elastic head. The handle containing the release mechanism is sandwich-assembled to the barrel so as never to be subjected to bending, thus obtaining an absolute rigidity of the whole. The standard head is of the "minimalist" type and can house two circular elastics. (Only size 90) The handle is fitted with the now tested "ONE" mechanism with great release sensitivity. The stainless steel rod equipped with 2 fins is 6.3 mm. Three sizes available: 80, 90 and 100 cm.