Couplers, strain relief hubs, and nose pieces for an ablation catheter assembly and methods of using the same

A medical probe comprising:

• a handle extending from a proximal portion to a distal portion;
• a shaft extending from the distal portion of the handle and coupled to a proximal portion of a balloon disposed at a distal portion of the shaft;
• a coupler disposed between the shaft and the proximal portion of the balloon, the coupler comprising:
• a first portion having a first aperture disposed therethrough;
• a second portion slidably coupled to the first portion and having a second aperture disposed therethrough and a spring recess;
• the second portion sized to be inserted at least partially into the first portion, the second portion configured to slide between a first position and a second position relative the first portion;
• a vent port proximate a proximal end of the second portion, the vent port configured such that when the second portion is in the first position, the vent port is at least partially obstructed by the first portion, and when the second portion is in the second position, the vent port is unobstructed by the first portion;
• and
• a spring received by the spring recess in the first position to prevent the second portion from moving to the second position unless a predetermined force is applied to either the first portion or the second portion.