A4 (Warning—Ascent) is a Swedish road sign belonging to category A (Warnings signs). Closer provisions are given in the road sign ordinance (SFS 2007:90): The sign warns about a steep ascent. The number indicates the ascent as a percentage and shall be adjusted according to the local conditions.
transportstyrelsen.se 



Source materials for this file are available from Commons Archive:

Sweden road sign A4-1.eps
Government of Sweden