NANMAC'S Tire Probe is a grounded thermo-couple junction located at the tip of a sharp-pointed stainless steel probe. The 0.040" diameter by 0.1" long probe is rigidly bonded to the plastic handle. Penetration is automatically limited to 3/8" max. by the 1/4" diameter stainless steel shoulder. Response times of about one second are easily obtained by this probe. All probe assemblies come fully assembled with a plastic handle, stress relief spring, 12" of retractable extension lead and a miniature male 2-prong connector.