Abstract: Disclosed herein are catheters having multiple coil layers, and associated systems and methods. In some embodiments, a catheter includes an inner liner, a plurality of wires over the inner liner, and an outer sheath over the wires. The wires are coiled about a longitudinal axis of the catheter in a first direction to form a first coil layer over the inner liner, and the wires are coiled about the longitudinal axis in a second direction, opposite the first direction, over the first coil layer to form a second coil layer over the first coil layer. The wires each include a continuous/self-terminating end portion wherein the wire switches from the first direction to the second direction and transitions from the inner coil layer to the outer coil layer.

Abstract: A roller-style firearm trigger mechanism is disclosed. The trigger mechanism includes a sleeve or bearing which freely spins or rotates around a pin or shaft or that freely spins or rotates within a receptacle that is positioned along, or that replaces, the portion of the firearm trigger that the shooter's trigger finger would normally touch during firearm discharge.