This is a six (6) pack of a filters that work with the following Philips Respironics machines:

• All PR System One Series
• All PR System One 60 Series
• SleepEasy II
• SleepEasy

This filter does not have a tab.

Tips for inserting filters:

1. If you are using a disposable white filter with the PR System One, PR 60 Series or SleepEasy machine, insert it into the filter area before adding the foam, washable filter.
2. Insert the white filter with the fibrous, stiffer side facing in, towards the device and the papery, softer side face out.
3. Insert the gray or black foam filter into the filter area, on top of the fine filter.