3M™ E A RLINK™ Foam Eartips 3A 420 2004, with Black Tube, Adult Size Sanders & Grinders They are "electronic passive" earmuffs 31 21 160 They are "electronic passive" earmuffs The 3M 8822 Disposable Respirator FFP2 provides lightweight Infant Eartips are designed to be used as an alternative for the foam (E A RLINK™ ) eartips connected to the E A RTONE™ Insert Earphone in instances where the smallest (3B) foam tip size is too large for the test subject's ear canal the E A RTONE™ 3A and 5A Insert Earphone for audiometric testing provide both performance and reliability advantages over traditional supra aural earphones