The PrimoChill Rigid Tube Silicone Bending Insert Tube - Expert is used for bending the PrimoChill Rigid Tubing (3/8 in. ID). This insert allows the rigid tube to be heated and bent with minimal tube deformation in the bends. The tighter fitting expert insert allows for flawless bends. Experience in bending rigid tube is needed if you plan on using this bending insert as it is more difficult to insert and remove. Features Durable Elastic Silicon Material Specifications Color: Black Compatibility Tube: 3/8in. ID Acrylic/PETG Tube only Parts Included Single 3 Foot Piece Bending Insert Tube Expert Warnings PrimoChill is not responsible for any damage caused by or when using this product. Please use at your own risk. Installation The bending insert is meant to have a tight fit. If it is loose, the rigid tube will collapse, kink, form air pockets and flat spots. The tighter the fit, the better the result. This process requires patience, but will become easier the more you practice.The bending insert requires some stretching and lubricating to get it in the rigid tube.Steps to success are below:1. Stretch the bending insert. Remove any excess that isn't stretched. 2. Ream the rigid tube with an RFB for best results, (or a hand reamer if that's all you have). This will ensure a clean opening for easier insertion. 3. Lubricate by applying several drops of dish soap or olive oil on the bending insert itself and then place several more drops into the rigid tube. 4. Work the bending insert into the rigid tube. The more you use the insert, the easier this process will become.