The Fluke BP881 is a BNC Male to Double Stacking Banana Plug.

Product Details:
Allows for hands-free testing in controlled voltage environments 500 VRMS maximum.
Banana plug is nickel-plated, beryllium copper for low contact resistance
The BNC shell is plated for tarnish resistance
Operating temperature +50 °C (+122 °F) maximum

Designed to easily connect your DMM to a BNC patch cord. Use this adapter when connecting accessories that have a male BNC output.