Quantity   Component name
1 × ABS 3D Printing filament I used an entry level 3D printer and cheap filament, so nothing special unless you want to try and improve.
1 × Smooth-On Ecoflex™ 00-30 Platinum Cure Silicone Rubber https://www.smooth-on.com/category/platinum-silicone/
1 × Smooth-On Silc Pig Silicone Rubber Pigment https://www.smooth-on.com/category/color-and-fillers/
1 × mold release agent (must be non-silicone based) many mold release agents are silicone based, but since we are casting silicone these will make the silicone stick to the mold
1 × super thin spring steel from cheap/small retractable USB cords I don't like using cord with 3D printed prosthetics. I've had good luck with super thin spring steel from things that automatically retract (tiny tape measures, retractable cords etc.)
1 × large vacuum seal storage bag with hand pump These are usually used for backing clothes. I use them for creating a vacuum around the silicone rubber skin mold. They cost about $15 on Amazon/Ebay/Walmart including hand pump.