K Series Lineup: Unveiling the Gems
The Honda K Series engines made their debut in 2001 with the introduction of the K20A2 engine, a 2.0-liter inline-four that marked a paradigm shift in the world of compact performance. The K Series family expanded over the years to encompass various iterations, each offering unique characteristics suited for different applications. While the K20A2 is one of the most notable, other engines like the K20Z3, K24A2, and K24A1 have also left their mark.

Basically the K-Series’ fingerprint for the inline 4 engine from Honda
Source: Honda