I have been using these for about an year now, and they are the best ones under $40 that I've owned. Here are some plus points:
1. very sturdy metal band resulting in a snug fit
2. compact enough to be carried around, without loss in the bass! :)

Just be careful not to open the headphones holding the plastic parts - they may break. The best way is to hold the metal band and pull them apart. A very good buy, and highly recommended.

-Amarendra

Love these, incredible sound and even like the 80's look; unfortunately I currently am sending these in to be repaired, but with a LIFETIME WARRANTY there has been no hassle and I had only to pay the shipping and handle charges of about $6 I believe, this is an awesome add bonus but I gladly buy these again even without that benefit.

PRO's:
Sound is near impeccable!
Great price!
Comfortable fit,
Hard to match!

The only CON i could imagine would be the sound leakage due to the open style, on ear fit.

THE KOSS PORTAPRO HEADPHONES HAVE AN EXCEPTIONAL SOUND,GREAT BASS. I WOULD HIGHLY RECOMMEND THEM. Koss PortaPro Headphones with Case

I won't say anything more than the positive reviews here. I have had a pair of PortaPros since 1998. I use them everyday to go to work on the trains. I literally wear them out in about a year and a half of heavy daily commuting use. The great thing is if you catch the cable on something or drop the ear pieces and they start buzzing or break something, they come with a lifetime warranty and you can send them in to Koss and they will send you a replacement all for $6. I have done this about 5 times in 9 years. Try that with Sennheiser!!

After hearing the crisp, full sound of my cousin's Koss PortaPro Headphones, I had to buy a pair of my own, especially after the fact that my awesome old Skullcandy headphones failed after 2 1/2 years of service.

Awesome, they arrived 4 days earlier than originally projected, so I open the box to find a shiny new pair of Koss PortaPros. I had about 5 minutes to sample the awesomeness before I had to go to work, so I fold them up (neat design, by the way)and fit them into the tight (as in physical, not fashionable) carrying pouch and set them on my dresser.

The next day, I have more time to actually use these guys, so I pull them out of the pouch. This is where I need to warn buyers before getting these headphones.

THE POUCH IS TOO TIGHT, WHEN YOU PULL THE HEADPHONES OUT, NO MATTER HOW CAREFUL YOU DO IT, ONE OR BOTH OF THE EARPIECES WILL SNAP WHERE IT SWIVELS.

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