I strongly recommend ordering the First Aid Kit to enable future repairs and modifications. It has various spare parts for future maintenance and repairs once production has long shut down (thousands of kits ordered so far!). It includes 10 barrels, 10 flippers with springs, 1 horizontal and 1 vertical stabilizer insert, and spare inner foam. I hope to be able to manufacture as many First Aid Kits and spare parts as possible to keep all these great Model F keyboards running decades from now.

Kits are compatible with both ultra compact or classic style keyboards. Did you know that every 2U and larger key (backspace-sized key) and larger can be split into two keys, and the sensing pads are already there? Just add a flipper and then you can add keys! (Example splittable keys: space bar, both shift keys, backspace, enter) “Split Right Shift” refers to the HHKB-style split right shift (1.75U+1U); if you have a JIS layout or other layout with a non-HHKB split right shift (1U+1.75U) then select the “Regular” option and not the Split Right Shift option.

What's included:
1 custom machine-cut inner foam, just in case the original foam loses its elasticity while remaining in its compressed state for years on end, you’ll have a spare. Foam may not retain compressibility for decades when it’s compressed inside the keyboard but can last a while in storage (not compressed in a keyboard). The foam helps hold the barrels in place; worn out foam may result in more wobbly barrels and keys.
10 flippers with springs, in case you accidentally bend a spring out of shape when removing a key or cleaning your F62 or F77 or want to mod your layout and split a shift/backspace in the future to get an extra usable key. If one of your keys gets caught on the spring when you’re cleaning it in the future and the spring gets bent out of shape, there is no fixing the spring unfortunately (alas from my personal experience!).
10 barrels in case you spill a sugary beverage and some of the barrels become sticky.
2 Extra stabilizer inserts – in case some fail or break when trying to remove them from the barrels to change a layout
An original Industrial SSK (just kidding!)

Not included but highly recommended to keep your keyboard running in the future, long after production has shut down:

• Additional rubber bumpers for the bottom of the keyboard, available in various heights
• Additional flippers with springs beyond the included 10 of this kit
• Additional barrels beyond the included 10 of this kit
• Spare USB-C controller, in case of chip failure (rare) or accidental damage (tripping over the cord, etc.)
• Transparent relegendable keys (in case you forgot to order a key that you wanted in the future)
• Solenoid driver and solenoid (not required but great to have!)
• Extra inner foam beyond the included one piece of spare foam – avoids wobbly keys when the foam loses compression set over time while installed in the keyboard (the type of foam used for this project seems to retain its compressibility in the long term when stored outside the keyboard)
• Spare custom-made 3 meter USB-C braided cable (in recent years the cables I’ve bought from various places do not seem to last more than a few years of daily usage before requiring replacement)
• Extra space bar tabs
• Extra stabilizer inserts beyond the one of each type included in the kit (in case you damage one when trying to remove it)
• Model F wire key puller – definitely recommended if you do not have one already, for removing keys to clean them

Important terms: All foam is considered to have cosmetic defects not limited to creases, scuffs, indentations, folds, lines, and overly compressed parts. Assume your foam will have these issues and that you won't get a replacement. The foam comes from the foam factory in sheets of a pre-made size. To minimize the waste of foam, the factory sometimes glues together the foam. In no way does any of this affect operation or longevity of the foam as the barrels actually secure the foam in place. The tooling for this foam was custom made and I am the only seller of Model F factory cut foam. The foam for the compact and classic keyboards is considered to be interchangeable, even though there are slight differences in the shape between compact and classic F104/FSSK for example (again, keep your scissors/cutter/craft knife handy since you may need to make some cuts to your foam to adapt it to your keyboard model); they are the same functionally to hold the barrels in place and you can’t request one or the other even if you purchased one design and received the other design foam.