For our customers who have older Model 202 Ozone Monitorsä (white select switch, serial numbers < 300), we offer a trade in for a new Model 205 Dual Beam Ozone Monitor™ for $3,000; This amounts to a $3,000 allowance for your used Model 202.  Instruments traded in are refurbished and either sold or used as rentals.  Refurbished Model 202 instruments sell for $3,000.

Newer Model 202 Ozone Monitors (black rotary select switch, serial numbers > 300) may be upgraded to Model 205 Dual Beam Ozone Monitors for $2000.