Models built 'out of the box' are built according to kit instructions, using no materials except those provided in the kit itself. In the past, there was some tendency to view 'out of the box' builds as simpler or of a lower standard of detail than modified kits (see below). However, recent trends in which kits contain over 1,000 individual pieces including parts from plastic, etched brass, and aluminum have given new meaning to the 'out of the box' build. Today, a stock kit can be very highly detailed.