3M® 4950 VHB® is a firm acrylic foam tape that is used for bonding a variety of substrates. 4950 is one of two VHB® go-to items. It is used over the 4941 family when firmness is preferred to conformability. The 4950 family has general purpose adhesive on both sides of a firm type foam. It is typically used on glass, metal and high surface energy plastic substrates. In many instances it can replace rivets, spot welds, liquid adhesives and other permanent fasteners.