The size designations of stainless steel loops are nominal. The actual volumes can differ from the theoretical designations because of the ± 0. 025 mm (0. 001") tolerance of the metal tubing bore. Accuracy of large metal loops (1. 0 mm, 0. 040" bore) is about±5%, intermediate loops (0. 5 mm, 0. 020" bore) ±10%,and small loops (0. 2 mm, 0. 007" bore) ±30%. Bore: 0. 30mm. Model 7725 Injector loops are not interchangeable with loops for the Model 7125. The port angle for the 7725 is 30° whereas the port angle for the 7125 is 20°, requiring the loops to have a different shape.