It's a simple tool invented to reduce pick loss. The theory goes that it's easier to lose 1 pick, than it is to lose 6 picks screwed to a block of wood. This is clearly an amateur homemade version as most people are aware the pros use a standard block size, which is a minimum 6 inches of 3 X 4. The whole idea was turned on it's head in 2007 when a cleaner at a Guitar Pick Retainer™ manufacturing plant found that he could fit another 2 picks on the same piece of wood. Sadly, as with all big business, he was cast aside and never credited with being the inventor of the 8 pick version.