"This first switch type is the TECSEE Purple Panda, which is also a tactile switch and features a large, round bump on its legs. Mechanical keyboard switches contain two metal leaves that complete a circuit when they come into contact, registering a keypress. Separating them is a pair of legs on the stem, the part that moves up and down in the switch until enough pressure is applied. In a linear switch, the edge of these legs is straight while a tactile switch, like these, has a curve or bump on them, which alters the amount of force it takes to move the stem and allow the leaves to touch. The size, shape, and placement of the bump all contributes to the exact feel of pressing the switch, with this large, round bump being something quite popular since the creation of the Holy Panda franken-switch. Fortunately these Purple Panda switches do not require combining parts from multiple switches to build, as those once did."



Link: OCC