These will be back soon!
Some switches that are placed with the LED facing the north (rear) of the board are plagued with interfering with certain keycaps. These washers are 0.25mm thick, and will slide over the MX stem to lift up the keycap and prevent it from hitting the housing, and ruining the feel of your favorite switches.
Each pack contains 120 washers, which is good for 60 switches - it’s recommended you use 2 per switch (a total offset of 0.5mm) to prevent all contact.