Abstract: A retractable reel includes a housing having a front cover and a rear cover, the rear cover including a first opening and the front cover including a second opening, a trough extending radially inward from the second opening to a center of the front cover, the trough including at least one tab and at least one dimple and a resiliently deflectable latch arm. A spool includes a wall that extends axially outward from a front surface of the spool, the spool is rotatably supported within the housing and is positioned such that the front surface, the wall and the front cover cooperatively define a chamber therebetween. The spool further includes at least one ratchet member selectively engaged by the resiliently deflectable latch arm to prevent rotation of the spool in a winding direction. The retractable reel includes a spring having a first end engaging the rear cover and a second end engaging the spool for rotatively biasing the spool in the winding direction.

Abstract: The present invention is a gas component sensor comprising novel electrolyte compositions. The electrolyte compositions in bulk, sintered or thin film embodiments are capable of forming with different-metal sensing and reference electrodes a highly stable gas oxide sensors. The novel electrolyte composition changes electrochemical reactions at the sensing and reference electrodes and the overall reaction of the electrodes and electrolyte. The novel electrolyte compositions have: (1) excellent chemical stability and thermal compatibility as to the electrodes and a preferred ceramic substrate, (2) excellent chemical stability with the environment as to the reference and sensing electrodes, which need not be sealed against the atmosphere to be sensed, (3) effective adherence to the substrate and electrode metals.