Bjorn's friend hands him a Leatherman Wingman, which is heavily used for over a minute in the show to cut hose and fashion a funnel from a soda bottle in order to repair a truck's antifreeze lines. It's best seen at 13:50-14:00, where the general format of the tool and partially serrated blade are seen.
IRR_LMW_1 by
cody6268, on Flickr
Oh, and I liked the comment "A greasy man with a knife is no good". That's how I bent the small blade tip on my old Fieldmaster--it slipped out of my hand and struck the concrete when closing the blade after cutting some cable ties of some hydraulic lines on the tractor. That's why my work SAKs all have nylon scales now. I like nice and shiny tools, but when you're hands are greasy, it's a mess.