Over the years, the rules have evolved to improve performance, lower cost, or to allow replacement of discontinued parts.

This allowed easier development and replacement of games, but it also discouraged the hardware innovation necessary to stay ahead of the technology curve.

This rifle has a modular construction which allowed easy replacement of components and caliber changes.

Within the US, some states allow amendments or complete replacement of the original birth certificates.

As of 2010 many P9RCs are still in service, for military and police fundings did not allow complete replacement.

And it should allow faster replacement of depleted bamboo forests that are vitally needed.

The buffer beam section is also a separate part, which allows replacement if it is damaged in a collision.

Wing Tips: These are removable assemblies to allow easy replacement in the event of damage.

It also allows easy replacement of a set of lenses if they are damaged.

The T41 allowed replacement of steam locomotives on non electrified lines.