Disclosed herein is an assembly for a side view mirror for a vehicle. The assembly comprises two arm members which are configured to receive a side view mirror thereat and a joining member for joining the arm members. The joining member comprises two sleeves, where each sleeve projects from a respective arm member and comprises an interlocking profile at a distal end thereof. The assembly also comprises a tightener configured for receipt through the sleeves when the sleeves are in an aligned configuration. Tightening the tightener draws the interlocking profiles of the aligned sleeves into engagement, whereby the arm members become rigidly joined.