The Etymotic Research ER-4P stereo earphones feature an ultra-lightweight design, 35 - 42dB of external noise attenuation and an enhanced output level for both the high and low frequency range. This is a combination that ensures clear, natural listening enjoyment at safe and moderate playback levels.
These earphones are specifically designed to accompany all manner of portable audio listening devices, with no additional amplification required.
| Type | Balanced Armature Stereo Earphones |
| Frequency Range | 20 Hz - 16 kHz, +/-4 dB |
| Impedance | 27 Ohms nominal |
| Sensitivity | 108 dB SPL/mW @ 1 kHz |
| Maximum Input Power | .75 Vrms |
| Connectors |
1 x Detachable 1/4" Stereo Phone Adapter 1 x 1/8" Stereo Mini Plug |
| Cable Length | 5' (1.5m) |
| Weight | 1 oz (28 g) |