Quoted from Pinwizkid:
A hobbyist named Lee Conklin made a similar product about a decade ago. He sold them in sets of 4 for about $35 and I have used them on almost every pin move since. Not sure if he still makes them, but none of them have broken and other collectors always ask me where they can buy them.
that's where he got the idea...
a fellow pinsider dropped off a game at my shop this past weekend and had the ones your talking about. i was amazed at how much easier it was to move! i offered to buy them, but he mentioned how he got them 10yrs ago, and hasn't seen them available since.
my employee's dad says, "i can make those in a coupl'a hours!". i didn't realize he'd actually go do it the very next day. so rad! for folks who move alot of games, i can't recommend these enough.