128GB 4K-compatible BD-R XL, a 3-pack for high-quality recording. - Brand: SONY - Model: BD-R XL - Capacity: 128GB - Pack Count: 3 Pack - Usage: For single recording - Supported Resolution: 4K - Write Speed: 2-4x These are high-performance Blu-ray discs with large capacity, allowing for 4x dubbing, but they are for single recording, so please use them to save important videos. Things like weddings or records of your children's growth, perhaps. These are made in Japan by the reputable SONY. If your recorder is also SONY, I've never had an error. Thank you very much. Thank you for viewing.