I purchased this from an electronics store about two years ago. Usage frequency: Only once after purchase. The sticker-type instruction manual attached to the main manual was originally included with the unit. The charger cord is not included because I have too many at home and can't figure out which one it is. Please use your own cord. *I have confirmed that it can be used with other cords I have. Below is the official description: Despite its compact size, the earphones alone provide up to 8 hours* of playback, and up to 27 hours* when used with the charging case. The open-type design makes it comfortable to wear for long periods without putting stress on your ears. Also, it supports quick charging, allowing for up to 60 minutes of music playback with a 10-minute charge, so you can use it immediately with a short charge. Openpiece Open-type Earphones TE-S1 Black Brand: AVIOT Wearing style: Separate left and right, completely independent Earphone/Headphone type: Canal type Color: Black Wireless/Wired connection: Wireless Earphone/Headphone features: Microphone, Sound quality adjustment, Waterproof, Splashproof, Remote control Wireless standard: Bluetooth Wireless function: Multi-pairing Bluetooth codec: AAC, SBC IP rating (waterproof rating): IPX4 Drive system: Dynamic type Driver size (mm): 10.0 mm Charging terminal: USB Type-C Charging time: 1.5 hours AVIOT TE-S1 black wireless earphones, with charging case and user manual. - Brand: AVIOT - Model: TE-S1 - Color: Black - Accessories: User manual, ear tips - Case: With charging case Original price: 9900 yen (tax included)