Description Description Freudenberg Sealing Technologies (formerly Tobul) adapter lock nut, zinc plated for TBRT30 Bladder accumulator Series. Zinc plated adapter lock nut minimizes vibration, corrosion, and helps to prevent loosening. State of California Proposition 65 WARNINGCancer and Reproductive Harm - www.P65Warnings.ca.gov. Literature & Docs Accessories