Sony PHDV-276DM 276 Min Digital Master HDV DVCAM Tapes Box of 10 The Sony PHDV-276DM 276 Minute Digital Master Videocassette is a professional videotape with 2 active magnetic layers, improving carrier to noise ratio by 2.5db for 95% fewer errors and 60% fewer dropouts than consumer DV tape. It uses AMEII metal Digital master videocassette is a professional tape designed for mastering and is also highly flexible and convenient media, enhancing compatibility between camcorder and VTR. AMEII metal evaporation technology has been used to improve the packing of grains inside the magnetic layer, increase tape retentivity (Br) and output as well as achieve better C/N and error ratios Quality control has been enhanced following a complete review of the production process, resulting in improved drop-out figures. Diamond-like Carbon protective layer on the tape surfacea dramatic improvement in wear resistancehas been achieved, resulting in reduced head wear.