Photonbox Leica ABLON 35mm film leader trimmer guide.
If you shoot with early Leica screwmount cameras (Leica I, II, III series) this is extremely handy to prepare the film leaders of your modern film cannisters before a shoot.
Simply extend the film leader to the end of the guide, close the guide ensuring the pins go through the film sprocket holes, and use a knife/X-acto blade to trim the correct shape.