{"product_id":"usams-free-sr01-anc-noise-cancellation-headphones-over-ear-bluetooth-compatible-music-earphones","title":"USAMS Free SR01 ANC Over-Ear Headphones – -25dB, 40H Play, 350mAh","description":"\u003cp\u003eThe USAMS Free SR01 are ANC over-ear wireless headphones in ABS. Driver: 40mm. ANC depth: -25dB. Playback time: approximately 40 hours. Talk time: approximately 35 hours. Battery: 350mAh. Charging time: approximately 2–3 hours at 5V\/0.3A. Supported codecs: AAC and SBC. Weight: approximately 124.8g. Size: 176×172×40mm. Bluetooth version: not specified in source documentation (Bluetooth-compatible Name field shows device name 'SR01', not a version number). A charging cable is included in the package. No certifications listed. Package: headphones, charging cable, and English user manual. Curated by Aetheo.\u003c\/p\u003e\n\n\u003ch3\u003eWhy you'll like it\u003c\/h3\u003e\n\u003cul\u003e\n  \u003cli\u003e-25dB ANC — active noise cancellation for focused listening\u003c\/li\u003e\n  \u003cli\u003e350mAh battery — approximately 40 hours of wireless playback\u003c\/li\u003e\n  \u003cli\u003e40mm driver — AAC and SBC codec support\u003c\/li\u003e\n  \u003cli\u003eApproximately 35 hours of talk time per charge\u003c\/li\u003e\n  \u003cli\u003eCharging cable included — approximately 2–3 hours to full charge at 5V\/0.3A\u003c\/li\u003e\n\u003c\/ul\u003e\n\n\u003ch3\u003eDesigned for ANC wireless over-ear listening\u003c\/h3\u003e\n\u003cp\u003eThe Free SR01 uses Active Noise Cancellation rated at -25dB to reduce ambient background noise during listening. ANC works by sampling ambient sound via onboard microphones and generating an inverse signal to counteract it — most effective on steady low-frequency noise such as engine hum, air conditioning, and transport noise. The -25dB rating indicates the depth of reduction at optimal conditions on qualifying frequencies. The 40mm moving coil driver delivers audio with AAC and SBC codec support — Bluetooth version is not specified in source documentation. The 350mAh battery provides approximately 40 hours of wireless playback or approximately 35 hours of talk time; charging takes approximately 2–3 hours at 5V\/0.3A using the included charging cable. Sensitivity, impedance, and frequency response are not specified in source documentation. No certifications are listed in source. Curated by Aetheo.\u003c\/p\u003e\n\n\u003ch3\u003eKey features\u003c\/h3\u003e\n\u003ch4\u003e-25dB ANC — active noise cancellation for focused listening\u003c\/h4\u003e\n\u003cp\u003eThe Free SR01 uses Active Noise Cancellation rated at -25dB. ANC uses onboard microphones to sample ambient sound and generate an inverse signal to reduce it before it reaches the ear — most effective on steady, repeating low-frequency noise such as engine hum, road noise, air conditioning, and aircraft cabin sound. The -25dB rating is the stated depth of noise reduction. ANC supplements rather than replaces the passive isolation provided by the over-ear earcup seal; both work together to reduce ambient noise. ANC may affect battery life when active — the 40-hour playback rating is the stated figure; ANC-on vs ANC-off runtime split is not listed separately in source documentation.\u003c\/p\u003e\n\u003ch4\u003e40mm driver — AAC and SBC codecs — over-ear design\u003c\/h4\u003e\n\u003cp\u003eThe Free SR01 uses a 40mm moving coil driver. AAC and SBC codecs are supported for wireless audio transmission — AAC provides better quality than SBC at equivalent bit rates when paired with an AAC-capable source device. Sensitivity, impedance, and frequency response range are not specified in source documentation. Bluetooth version is not specified in source — the Bluetooth-compatible Name field in source data shows the device name 'SR01' rather than a version number. The over-ear earcup design positions the cups around the ear, providing passive ambient sound reduction from the earcup enclosure regardless of ANC mode. Actual audio codec used depends on what both the headphones and the source device negotiate at connection time.\u003c\/p\u003e\n\u003ch4\u003e350mAh battery — approximately 40H play, 35H talk — charging cable included\u003c\/h4\u003e\n\u003cp\u003eThe 350mAh battery provides approximately 40 hours of wireless playback or approximately 35 hours of talk time per full charge. Charging takes approximately 2–3 hours at 5V\/0.3A using the charging cable included in the package — the charging connector type is not specified in source documentation. Dimensions are 176×172×40mm; weight is approximately 124.8g. Sensitivity, impedance, and frequency response are not specified in source documentation. Call quality specifications beyond talk time duration are not listed in source.\u003c\/p\u003e\n\n\u003ch3\u003eBest for\u003c\/h3\u003e\n\u003cul\u003e\n  \u003cli\u003eANC focused listening — -25dB active noise cancellation for noisy environments\u003c\/li\u003e\n  \u003cli\u003eExtended wireless sessions — approximately 40H playback per charge\u003c\/li\u003e\n  \u003cli\u003eCall-capable wireless headset — approximately 35H talk time\u003c\/li\u003e\n  \u003cli\u003eAAC + SBC wireless audio — over-ear design with passive isolation\u003c\/li\u003e\n  \u003cli\u003eIncluded charging cable — 350mAh, approximately 2–3 hours to full charge\u003c\/li\u003e\n\u003c\/ul\u003e\n\n\u003ch3\u003eWhat's included\u003c\/h3\u003e\n\u003cul\u003e\n  \u003cli\u003e1 × USAMS Free SR01 Headphones\u003c\/li\u003e\n  \u003cli\u003e1 × Charging Cable\u003c\/li\u003e\n  \u003cli\u003e1 × English User Manual\u003c\/li\u003e\n\u003c\/ul\u003e\n\n\u003ch3\u003eCompatibility and setup\u003c\/h3\u003e\n\u003cp\u003eMaterial: ABS. Bluetooth: version not specified in source (Bluetooth-compatible Name: SR01). Driver: 40mm. ANC depth: -25dB. Codecs: AAC, SBC. Battery: 350mAh. Playback: approx. 40 hours. Talk time: app\u003c\/p\u003e","brand":"USAMS","offers":[{"title":"Default Title","offer_id":55110954811726,"sku":"6812002738A","price":48.0,"currency_code":"USD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0870\/2302\/6510\/files\/6812002738A-1.jpg?v=1762765542","url":"https:\/\/aetheo.com\/products\/usams-free-sr01-anc-noise-cancellation-headphones-over-ear-bluetooth-compatible-music-earphones","provider":"Aetheo","version":"1.0","type":"link"}