Kenny Steigerwalt/Matthew Lerch "Flipper" Assisted Opener; Ken and Matt collaborated on this new type of double spring assisted opening mechanisim, and have patented it; the knife works super good and is a great design; the 4" hand ground blade is S30V SS; handle is titanium; it is mostly a handmade knife, but the parts were cut with a laser and waterjet; there are a few dealers out there that might not tell you about that, but I believe in full disclosure; great knife for Price $550