43 PTFE SOLID BACKUP RING FDA

APG stocks the TST043SO, an AS568-043 white PTFE (Teflon) 55 Shore D Back-Up Ring measuring an inside diameter of 3.489 in (88.62 mm), a cross section of 0.07 in (1.78 mm), and an outside diameter of 3.629 in (92.18 mm). A back-up ring allows a standard o-ring to operate at higher pressures than it could unsupported.

PTFE (Teflon) is known for excellent dielectric properties and one of the lowest coefficients of friction of any solid. The compound resists strong acids and bases, nearly all industrial chemicals, and steam. Rated temperature range runs from -65°F (-53.9°C) to 500°F (260°C) in continuous service.

Maintenance and OEM teams specify it across aggressive-media pipelines, laboratory equipment, and food and beverage.

Reference part number TST043SO when ordering; the item is sold individually. Check the compound against your process media, pressure and temperature before committing to a design. APG supports cross-referencing from drawings, samples and competitor numbers when a listed size is not an exact fit.