The Orion optical sensor cap has a life of 24 months from the date of manufacture, or 12 months from the first reading, whichever comes first. To guarantee accuracy and a full 12-month working life, the customer should store the cap in its factory packaging prior to use, and install by the date printed on the label.
The Orion optical sensor cap is very robust and resistant to damage. A maximum storage time of 12 months prior to installation is recommended so that a full 12 months of cap usage is achieved. Therefore, it is not advisable to stock a large quantity of replacement caps, unless your monitoring conditions necessitate this.