Selangor's B is where the system discovers what "too many cars" actually means.

The state moved from SL to B in the same 1948 reform, and then did what Selangor always does: outgrow the format. By 1971, B has burned through the old capacity and becomes the first to move formally into three-letter combinations. That shift isn't cosmetic; it's the moment JPJ accepts that the simple structure will not survive the volume.

Because of that, B-series plates read differently from almost any other prefix. They are proof of pressure. For decades, B is one of the most common sights on the road, the workhorse series that forces the rules to stretch. A strong B plate doesn't need slogans attached to it; the history is built into how fast the codes had to turn over.