The Kilometre Zero of the Federal Route 20 starts at Northport Interchange near Port Klang.

By the 1990s to 2000s, the highway was bogged down with severe congestion, and the present New North Klang Straits Bypass was built to replace it.

At most sections, the Federal Route 20 was built under the JKR R5 road standard, with a speed limit of 90 km/h.

The bypass is not considered safe because of many accidents involving heavy vehicles along this road, especially the area around a school.

On 18 May 2005, on Teacher's Day, a seven-year-old girl from Sekolah Rendah Agama Rantau Panjang religious school Nur Salina Saparedi was knocked by a lorry while she was crossing this road.