External stowage platform

External stowage platforms (ESPs) are key components of the International Space Station (ISS). Each platform is made from steel and serves as an external pallet that can hold spare parts, also known as orbital replacement units (ORUs), for the space station. As a platform it is not pressurized, but does require electricity to power the heaters of some of the stored equipment. ORUs are attached to the ESP via Flight Releasable Attachment Mechanisms (FRAMs), matching witness plates that mate the ORU to the platform.

External stowage platform

External stowage platforms (ESPs) are key components of the International Space Station (ISS). Each platform is made from steel and serves as an external pallet that can hold spare parts, also known as orbital replacement units (ORUs), for the space station. As a platform it is not pressurized, but does require electricity to power the heaters of some of the stored equipment. ORUs are attached to the ESP via Flight Releasable Attachment Mechanisms (FRAMs), matching witness plates that mate the ORU to the platform.