How to choose the correct PVC Bendit.
You need to consider the smallest diameter PVC pipe you will be bending and also the length of pipe. So, the alpha character (A or B) in our part number represents the diameter of the PVC Bendit. The A is slightly 7/16" OD while the B is 1.06" OD. The numeric (3,6,9,10,20) represents the length of the heating surface of the PVC Bendit. The overall length will be two feet longer as there are non heated sections at each end. The element in the B series generates more heat than the A series but either is adequate for most diameters of PVC pipe.
If you are bending 1/2 inch and larger diameter pipe you should select the A series and then select the length based on the length of pipe you will be bending. The A Series comes in 3, 6, 9 and 10' lengths.
If you will be bending 1-1/4 and larger PVC pipe you will want the B Series which has an Outside Diameter of 1.06". Then select the length based on the lengths of pipe you'll be bending. You can use a longer Bendit in a shorter pipe but not vice versa.