Chambers often have multiple ports, covered with vacuum flanges, to allow instruments or windows to be installed in the walls of the chamber.

This allows other instruments on the rover to take unobstructed images and measurements of the minerals inside.

If abnormalities are found, an operative hysteroscope with a channel to allow specialized instruments to enter the cavity is used to perform the surgery.

This in turn allowed musical instruments, besides the organ, to be employed in the music.

They are also small and can operate at room temperature to 45C, allowing instruments to be made much smaller, even to fit on a lab bench.

Dilatation ("D") is a widening of the cervix to allow instruments into the uterus.

An optical window may be built into a piece of equipment (such as a vacuum chamber) to allow optical instruments to view inside that equipment.

If they allow instruments into prisons, that is.

This feature allows software-based musical instruments to be played, sequenced, and recorded inside of Mixcraft.

Some competitive circuits also allow electronic instruments such as synthesizers and bass guitars, which are typically part of the front ensemble.