Exclusive Nellcor-Puritan Bennett sensor port The versatile, handheld Oxitest Plus7 provides the most advanced technology available in the market today for verifying the proper operation and performance of pulse oximeter monitors and modules throughout the clinical environment. The Oxitest Plus 7 has an exclusive Nellcor-Puritan Bennett sensor port, which was developed in cooperation with Nellcor®. This Industry-exclusive feature allows correct selection of the instrument?s simulation output to the specific R-Cal value of the attached Nellcor® probe.