This is a brand new, unopened, and officially licensed domestic version of the "PORTA PRO," a long-selling and best-selling model from KOSS, also known as the "King of Cost Performance" in the United States. Originally a popular model, it has gained even more attention due to the recent retro boom, with many celebrities and influencers seen using it. The sound tends to have powerful and warm bass, making it a great match for modern music genres like EDM and hip-hop. Also, the driver unit size is the same as the popular "KSC75" model from the same company, although the sound characteristics are different (KSC75 has a high-resolution, cool sound suitable for classical, rock, and metal). Therefore, many people swap the units depending on their preference. The replacement method is very simple, just swap the units. If you have any questions or inquiries, please feel free to leave a comment. Thank you. Structure: Open-air Earphone/Headphone type: Headband Color: Black, Blue Earphone/Headphone features: Foldable Low-frequency range (Hz): 15 Hz High-frequency range (kHz): 25 kHz Drive system: Dynamic Plug shape: 3.5MM Impedance (Ω): 60 Ω Sound pressure sensitivity (dB): 101 dB Cord length (m): 1.2 m Weight (g): 60 g =========================== ・Returns and cancellations are not accepted. ・Bulk purchases, dedicated listings, and various event support are possible (category changes, relisting, etc.). ・If you purchase with other items, we will discount the shipping cost. Please comment if you wish. ・We are also listing on other platforms, so we may delete the item without notice if it sells out. #koss #ksc75 #portapro #porta #pro #retro #style #wired #on-ear #open-air #headphone #headphone #retro #retroheadphones #retroheadphone