1/6 Watt, +/- 5% tolerance PTH resistors. Commonly used in breadboards and perf boards, these 330Ohm resistors make excellent LED current limiters and are great for general use.
We've opted for a new and more breadboard-friendly lead thickness (they're a bit thicker ...but not as thick as yo mama).

Note: Although these come in bags marked with a quantity of 25, they don't always contain 25. So we'd rather call it 20 and hope that you get extras.