A cryosurgical probe assembly that includes a gas delivery assembly, including a stem and a fluid conduit subassembly bonded to the stem. The fluid conduit subassembly delivers and returns cooling fluid used for cryogenic cooling. The fluid conduit subassembly, comprises a shaft for providing a heat exchange surface for cryogenic ablation; a housing securely connected to said shaft; and, an insulation element slideably engaged with an inner surface of the shaft and slideably engaged with the stem. The cryosurgical probe assembly includes an adjustable sliding apparatus that includes a slider assembly securely attached to said insulation tube for slideably guiding the insulation tube along said shaft; and, a button assembly operatively connected to the slider assembly for allowing a user to actuate the slider assembly to provide a desired adjustment of the insulation tube relative to the shaft. A handle assembly is positioned about the housing.