These are stabilizers using genuine Cherry Clip-in housings, used to stabilize the longer keys on your keyboard.
2U stabilizers are available with silver wires, sourced from Cherry.
6.25U, 7U, and 2U stabilizers are available with black wires, designed to meet cherry spec by CannonKeys.
Available in 6.25U, 7U, and 2U lengths, these stabilizers come as PCB mount clip-in only.
Black wires are also available standalone for purchase here.
A Standard 60% board typically needs 4x 2u stabilizers and 1x 6.25u stabilizer. A Tsangan/HHKB/WKL 60% board needs 2x 2u stabilizer and 1x 7u stabilizer. A full sized board typically needs 7x 2u stabilizers and 1x 6.25 stabilizer.