Here are some of the parts variations among the various models of the 99 rifle.

 Picture number 601 (picture courtesy of Shannon Zeigler) shows an early Model 99 bolt and dustcover.

Picture number 602 (picture courtesy of Shannon Zeigler) shows the disassembled bolt. Note the small number of parts. Disassembly of the bolt can be done without tools and in a matter of seconds.

Picture number 603 (picture courtesy of Shannon Zeigler) shows an early style safety and a transitional style safety.

Picture number 614 (picture courtesy of Shannon Zeigler) shows later model safeties.

Picture number 604 (picture courtesy of Shannon Zeigler) shows an early cleaning rod and a later short cleaning rod.

Picture number 605 (picture courtesy of Shannon Zeigler) shows several varieties of short cleaning rods.

Picture number 606 (picture courtesy of Shannon Zeigler) shows a number painted on a buttstock. The number below the katakana in the circle is the number 018.

Picture number 610 (picture courtesy of Earl Battey) shows the different variations of buttplates - left, the regular cupped buttplate, middle, the thin cupped buttplate as found on some 7^th series Model 99 rifles, right, the wooden buttplate which was nailed to the buttstock.