Teflon bars ideal for inserts, its main characteristics are: very low shrinkage, resistant to high temperatures and when extracted from the piece does not leave marks, getting excellent finishes.
Silicone cord for inserts. It has the advantage that being flexible facilitates the extraction of the piece with greater facility.
Silicone for inserts. It has very good mechanical and thermal resistance. For pieces that are difficult to extract due to their morphology, it avoids the breakage of moulds, thus extending their life.