This ProMediaGear PBSA7R Sony Alpha 7 a7 Series a7 a7r a7sBracket Arca-Swiss Style Plate is custom fitted for Sony Alpha 7 Series 7a 7r 7s. The bracket plate can be mounted to ProMediaGear flash brackets or L-Brackets. Since it is  custom designed it fits like a glove perfectly matching the camera shape, it also provides anti-rotation so the plate won't slip or twist. The plate has been machined from solid Aluminum T6061 block and has hard black anodized surface coating  for scratch resistant finish. The plate also features 1/4-20 threads for mounting other quick release plates or accessories.