A distal shaft for measuring pressure distally of a stenosis includes a housing, a pressure sensor, a cover, a tip, and an aperture. The pressure sensor is mounted in the housing. The cover is coupled to the housing and covers the pressure sensor. The tip is coupled to a distal end of the housing. The aperture is disposed through the tip and/or cover. The aperture is configured to allow blood flow to the pressure sensor. The cover further includes a coupling mechanism or coupling that couples the cover to the housing. The coupling mechanism may be a snap-fit mechanism, a friction-fit mechanism, and/or an adhesive.
