sennheiser is in the league of Shure, ultimate ears etc. they make perfect products.
Short Description
The foldable PXC 300 headphones with NoiseGard™ Advance active noise cancelling technology let you enjoy music in the most distracting environments. They reduce unwanted noise by up to 80% and the optimized circuit technology ensures reduced susceptibility to mobile phone interference. The PXC 300 is supplied complete with a protective soft case, batteries and aircraft audio adaptors.
Features
Closed, supra-aural mini headphones with switchable NoiseGard™ Advance active noise canceling technology
Advanced Circuit Technology (ACT): reduced susceptibility to mobile phone interference
The ultimate in portability; patented folding mechanism and protective case for storage and transportation
Ultra-lightweight design with ergonomic headband, two-point suspension and soft high-quality ear cushions for improved passive attenuation and superb wearing comfort
Duofol diaphragms with spiral embossing deliver transparent and lifelike audio reproduction with deep bass response
Supplied with ¼ inch adapter and airline audio adapter (dual 1/8” jacks)
Requires (2) AAA batteries for NoiseGard operation (included)
2-year warranty
PXC300 versus PXC250: The PXC300 delivers deeper bass response, increased noise cancellation, thicker, softer earpads, a hard shell case and the ACT circuit (see above).
More Info about Sennheiser's PXC Noise Cancelling Models