NewFantasia Replacement Audio Upgrade Cable for Sennheiser HD4.40, HD 4.40 BT, HD4.50, HD 4.50 BTNC, HD4.30i, HD4.30G Headphones 1.2meters/4feet

I can confirm that this cables works with the Sennheiser HD400s headphones. It fits into the 2.5mm port and rotates/locks in just like the cable that comes standard with the headphones.I was having issues with the original cable when plugging into certain devices or extension cables, and this takes care of that. I got the 3 meter length cable, and now I can plug my headphones into my PC speakers and listen to music from my bed which is what I wanted to do all along with the HD400s.Lastly, I'll say the build quality matches the price. I wish I didn't have to spend $20 to get the full experience out of these headphones, but this cable is definitely an improvement over the standard one in all regards. The cable sleeve feels really durable, and the cable itself is surprisingly light and flexible.Two thumbs up for anyone looking to replace the stupid cable that comes with the HD400s.

EDIT: I apologise for the bad review. It turns out I was listening to YouTube while on a call, and the call was making the audio sound bad for some reason. The cable is fantastic; the audio sounds good, and it is sturdy and flexible. It fits snugly in my phone with no chance of falling out.Below is my original review, ignore that. That was purely user error.The cable works, I guess, but it's far too bad for me to say it's worth buying. The sound quality is TRASH. This isn't a defect with the headphones audio port, my HD 4.50 BTNC sounded great with the original cable. I would avoid this product

Got these to replace my old cord for my Sennheiser headphones. Wow, what a difference. They even sound noticeably louder now.The hole slot on my headphones is CRAZY deep and so I had to push them totally into the hole, they are absolutely completely buried in there, but all words great! The cables are made strong, able to withstand some occasional abuse. So under normal wear, even with daily use, these will last you for years.The 0.25" / 6.35mm plug adapter screws on, so it's very secure.

I'll keep it simple, the cable itself fits, works and seems well made. The included 1/8" to 1/4" adapter may not work for you.When I initially used it I plugged it into my preamp 1/4" headphone jack using the included adapter and only had sound from the right ear. Bummer. Tried it with a different 1/4" adapter and it works. If I use the included adapter, fully seat it, and then pull it out about 1/16", I then get both channels, so it may be my preamp.Tried it with the 1/8" plug directly to my laptop headphone jack and it also works just fine. Haven't tried it in a plane headphone jack, but I imagine it will work fine there too.The locking mechanism into the headset itself also works, but takes a little effort to get the plug to seat fully before you can turn it to lock, but this loosens up after a few uses. Not quite as good as the OEM but nothing ever is.All in all satisfied with the cable itself, not the headphone 1/8" to 1/4" adapter. YMMV as this may be my specific preamp jack not being compatible with this particular adapter.

Work fine for about 2 weeks or so, then sound starts cutting off on the left side. Eventually, sound is totally cut off unless I manually hold the cord at the point of contact with the headphone in a certain angle. If I let go of the cord, no sound coming out of the headphone. Assembly was terrible.

I purchased SENNHEISER Headphones model HD 4.50 BTNC. I nearly returned them because the cable that was included with the headphones did not fit properly in the 2.5mm headphone jack. After trying some other cables that also did not fit, I was certain that I would have to return these headphones. Then I discovered this replacement cable ... the "NewFantasia Replacement Audio Upgrade Cable for Sennheiser HD 4.50 BTNC". It fit perfectly ... nice and snug. If you look close at the jack, there are nibs that act as a locking mechanism. And if you look close at the 2.5mm plug on this replacement cable, you can see where the nibs fit into slots. When you insert this replacement cable into the headphones, you have to turn them until they lock. I'm somewhat annoyed that SENNHEISER packaged such a poorly-designed cable with these HD 4.50 BTNC headphones, but I'm thankful that I found this replacement cable ... it's exactly what I needed. (BTW, 95% of the time, I use the Bluetooth connection, but there are times when a cable is necessary, such as when I'm playing my guitar into my headphones.)

They work so well. The jacks fit in the socket of the airplane. Since there are 2 sizes, it will fit in other airlines..My husband had been looking high and low. When I found these I ordered them and we have never regretted it. 5****

I got these expecting a cheap generic replacement cable, and what I got is far better than what was originally included with my headphones. The cable is thick with a fabric sheath, and the connections are solid on both ends. I really whacked the 3.5mm plug a couple of times now, and it bent a little, but didn't break yet. I'm very happy with this purchase.