Hario Slim Grinder Lid Clip

I have had a Hario Slim Coffee Grinder for years. It works great - I use it a couple of times a day to make my espresso and not too much noise in the house. I also like to use it when I travel outdoors or camping using my Aeropress. Anyway the hopper lid only sits on top of the grinder and so I usually use rubber bands to hold it in our picnic bag to avoid beans from going everywhere - though because of the elongated shape they are hard to actually keep on.

So I figured if I designed and pr