{"product_id":"usams-yh21-bluetooth-compatible-over-ear-headphones-hifi-stereo-headset-70h-long-playtime-hands-free-calls","title":"USAMS YH21 Bluetooth 5.3 Over-Ear Headphones – 500mAh, 70H Playtime, 40mm Driver","description":"\u003cp\u003eThe USAMS YH21 are Bluetooth 5.3 over-ear headphones in ABS+PC. Driver: 40mm. Speaker sensitivity: 108±3dB\/1kHz at 0.179V. SNR: ≥80dB. Connection range: ≤10m. Battery: 500mAh. Playback time: approximately 70 hours. Call time: approximately 60 hours. Charging time: approximately 3 hours at 5V\/0.5A. Size: 167×186×80mm. Weight: approximately 223g. Colour: Black. Wired mode is described in source but a wired cable is not included in the package. No certifications listed. Package: headset and English\/Chinese manual. Curated by Aetheo.\u003c\/p\u003e\n\n\u003ch3\u003eWhy you'll like it\u003c\/h3\u003e\n\u003cul\u003e\n  \u003cli\u003e500mAh battery — approximately 70 hours of wireless playback per charge\u003c\/li\u003e\n  \u003cli\u003e40mm driver — wide frequency response with structured low-frequency output\u003c\/li\u003e\n  \u003cli\u003eBluetooth 5.3 — stable pairing with connection range up to 10m\u003c\/li\u003e\n  \u003cli\u003eOver-ear design — cushioned earcups for extended-wear comfort\u003c\/li\u003e\n  \u003cli\u003eRetractable arms — adjustable to different head sizes\u003c\/li\u003e\n\u003c\/ul\u003e\n\n\u003ch3\u003eDesigned for extended wireless listening\u003c\/h3\u003e\n\u003cp\u003eThe YH21 connects via Bluetooth 5.3 to smartphones, tablets, and other Bluetooth-enabled devices within a connection range of up to 10m. The 40mm moving coil driver delivers audio across the earphone's frequency range — speaker sensitivity is rated at 108±3dB\/1kHz at 0.179V with an SNR of ≥80dB. The 500mAh battery provides approximately 70 hours of playback or approximately 60 hours of call time per charge; charging via the 5V\/0.5A input takes approximately 3 hours. The ABS+PC over-ear design is 167×186×80mm and weighs approximately 223g. The retractable arms adjust to different head sizes. Source copy describes a wired mode for continued listening when the battery is depleted — a wired cable is not included in the package, and the headphone input jack type for wired mode is 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\u003e40mm driver — 108±3dB sensitivity — SNR ≥80dB\u003c\/h4\u003e\n\u003cp\u003eThe YH21 uses a 40mm moving coil driver with a sensitivity rating of 108±3dB\/1kHz at 0.179V and a signal-to-noise ratio of ≥80dB. The 40mm driver size is standard for full-size over-ear headphones and supports a broader soundstage than smaller drivers. Driver frequency response range is not specified in source documentation — the rated sensitivity applies at 1kHz. The over-ear earcup design provides passive noise isolation by surrounding the ear with the cushion pad, reducing ambient sound reaching the driver.\u003c\/p\u003e\n\u003ch4\u003e500mAh battery — approximately 70H playback — Bluetooth 5.3\u003c\/h4\u003e\n\u003cp\u003eThe 500mAh lithium battery provides approximately 70 hours of wireless playback or approximately 60 hours of call time per full charge. Charging takes approximately 3 hours at 5V\/0.5A — a USB cable is required but not included in the package. Bluetooth 5.3 connects to paired devices within a range of up to 10m; actual range varies with environmental obstructions. Codec support (SBC, AAC, aptX) is not specified in source documentation. The YH21 supports hands-free calls via the built-in microphone — microphone specification is not listed in source documentation.\u003c\/p\u003e\n\u003ch4\u003eOver-ear design — retractable arms — ABS+PC construction\u003c\/h4\u003e\n\u003cp\u003eThe YH21 weighs approximately 223g and measures 167×186×80mm in its default position. The retractable headband arms adjust the headband to different head sizes. The earcup material type (foam, leatherette, fabric) is not specified in source documentation. Source copy describes the cushions as reducing ambient noise after wear — this is passive isolation via the over-ear form factor, not active noise cancellation (ANC). Source also describes wired mode as available for continued listening when the battery is depleted; the wired cable is not included in the package and the input jack type is not specified in source.\u003c\/p\u003e\n\n\u003ch3\u003eBest for\u003c\/h3\u003e\n\u003cul\u003e\n  \u003cli\u003eExtended wireless listening sessions — approximately 70H playback on a single charge\u003c\/li\u003e\n  \u003cli\u003eHands-free calls — Bluetooth 5.3 with built-in microphone\u003c\/li\u003e\n  \u003cli\u003eOver-ear passive isolation — cushioned earcup design\u003c\/li\u003e\n  \u003cli\u003eAdjustable fit — retractable arms for different head sizes\u003c\/li\u003e\n  \u003cli\u003eCompact wireless audio — 40mm driver, 500mAh, BT 5.3\u003c\/li\u003e\n\u003c\/ul\u003e\n\n\u003ch3\u003eWhat's included\u003c\/h3\u003e\n\u003cul\u003e\n  \u003cli\u003e1 × USAMS YH21 Headset\u003c\/li\u003e\n  \u003cli\u003e1 × English and Chinese User Manual\u003c\/li\u003e\n\u003c\/ul\u003e\n\n\u003ch3\u003eCompatibility and setup\u003c\/h3\u003e\n\u003cp\u003eMaterial: ABS + PC. Bluetooth: 5.3. Connection range: ≤10m. Driver: 40mm. Sensitivity: 108±3dB\/1kHz at 0.179V. SNR: ≥80dB. Battery: 500mAh. Playback: approx. 70 hours. Call time: approx. 60 hours. Charging: 5V\/0.5A, approx. 3 hours. Size: 167×186×80mm. Weight: approx. 223g. Colour: Black. Codec: not specified in source. Wired mode: described in source; cable not included; jack type not specified. Certifications: not listed. Included: headset, English and Chinese manual.\u003c\/p\u003e\n\n\u003ch3\u003eWhy choose the USAMS YH21?\u003c\/h3\u003e\n\u003cp\u003eThe YH21 is a Bluetooth 5.3 over-ear headset — ABS+PC, 40mm driver, 108±3dB\/1kHz at 0.1\u003c\/p\u003e","brand":"USAMS","offers":[{"title":"Black","offer_id":55110768034126,"sku":"681700512A","price":50.0,"currency_code":"USD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0870\/2302\/6510\/files\/681700512A-1.jpg?v=1762765043","url":"https:\/\/aetheo.com\/products\/usams-yh21-bluetooth-compatible-over-ear-headphones-hifi-stereo-headset-70h-long-playtime-hands-free-calls","provider":"Aetheo","version":"1.0","type":"link"}