OvisLink OVHS072-V25 is designed directly connect to home office telephone's 2.5mm headset jack; no amplifier is needed. It comes with 2.5mm quick disconnect cord with volume and mute control. With its lightweight over-the-head leatherette earpiece design, you may wear it all day and feel comfortable.
AT&T ML17929, ML17939, 1040, 1070, 1080, 944, 945, 955, 964, 974, 984, 983, 993. AT&T cordless phones with 2.5mm headset jack
Panasonic KX-DT521, KX-DT543, KX-DT546, KX-NT543, KX-NT546, KX-NT551, KX-NT553, KX-NT556 and KX-NT560. Panasonic cordless phones with 2.5mm headset jack
And all telephones with 2.5mm headset jack.