Apollo 15 OPS surface + deepspace EVA used mylar - Al Worden edition

Used during three Apollo 15 lunar EVAs and a deep-space EVA

Exposed to the lunar environment for more than 18 hours and deep space environment during mankind's first deep-space EVA performed by Al Worden.

The OPS supplies the EMU with oxygen purge flow and pressure control for certain failure modes of the PLSS or PGA during EVA. In the event of a PLSS failure, the OPS flow is regulated to 3.7 +/- 0.3 psid for 30 minutes to provide breathing oxygen to the crewman, prevent excessive carbon dioxide buildup, and provide limited cooling.
In the lunar EVA configuration, the OPS is mounted on top of the PLSS. During contingency EV transfer from the lunar module, however, the OPS is attached by straps to the lower front torso of the PGA.

Originally from the collection of Apollo 15 commander Dave Scott - own a piece of history :

Worn on the lunar surface by Scott as part of his PLSS and carried on the first lunar rover for a total of more than 18 hours then used again by Alfred Worden during his first deep-space EVA!

The aluminized mylar fragment comes from one of the inner layers of the beta cloth protection of the OPS and is mounted onto an 8x10 presentation.

Disclaimer: Although the original piece comes from the collection of Apollo 15 mission commander David Scott, Mr. Scott is not involved in this edition nor does endorse it.