The traffic sign you mentioned, multi-lane vehicles 1048-20, indicates that vehicles with multiple lanes are allowed in the indicated area. This sign typically appears in contexts where there are specific traffic rules or configurations for multi-lane vehicles, such as restrictions or permissions related to the use of certain lanes.

In general, this sign serves to inform drivers that they should be aware of the potential presence and movement of multi-lane vehicles around them. When driving in areas with this sign, it's essential to keep a safe distance from larger vehicles and be extra cautious, as they may have different handling characteristics compared to standard vehicles.

If you have any specific questions related to this sign or other traffic rules, feel free to ask!