If you truck in British Columbia, Canada, you may see some extra-long rigs on Highways 1 and 5 between Vancouver and Kamloops.

According to media reports, British Columbia’s transportation department is allowing a limited number of “Rocky Mountain doubles” to operate on those highways in a pilot program.

The Rocky Mountain configuration – which consists of a full-length, 45- to 48-foot trailer followed by a shorter, 26- to 29-foot “pup” trailer – allows an extra 20 feet beyond the standard double-trailer length, and is already legal in 20 states and some parts of Canada.