I found this on a data sheet
"The unique feature of the HPC series
cord plugs are the “push to lock” feature, similar to the
connection of an XLR connector. The HPC cord plugs, when
mated to either HPC panel mounts or Speakon® panel mounts
do not require a 1/4" turn to engage. Simply push the connector
in until it locks. To disengage, push forward on the latch lever
and pull the connector out. This feature eliminates the need to
remember to turn the connector to make contact. All HPC cord
plugs utilize 0.250" Faston® terminals, which allow for easy
assembly, and make it easy to change cord plugs. To change
from a straight cord plug to an in-line cord plug, back off the
strain relief nut, twist off the handle, disconnect the Faston®
terminals, fasten the new cord connector, twist on the handle
and the strain relief. Barbs on the handle keep the handle from
vibrating loose from the front shell.
Both HPC panel mounts and cord plugs incorporate a built-in
gasket, which allows them to meet IP 25 harsh environment
ratings, as well as IEC 529 and IEC 1010-1 safety ratings.