Description General description Heavy-wall borosilicate glass tubes are pressure rated to 150 psig. Useful for the polymerization and analysis of halogens by thermal decomposition in the presence of lime. Tubes are supplied complete with Ace-Thred PTFE bushing and FETFE® O-ring. For pressure work, the "Front seal" bushing is recommended (allows O-ring to sit at narrow neck of tube, below the threads). "Back seal" bushing can also be used, if preferred (allows O-ring to sit on top of the tube against cap). Replacement FETFE O-rings: Front Seal: Z504661 (Ace-Thred #7) Z504858 (Ace-Thred #15) Z505056 (Ace-Thred #25) Back Seal: Z504742 (Ace-Thred #7) Z505021 (Ace-Thred #15) Z505110 (Ace-Thred #25) CAUTION: This glassware is not guaranteed against breakage caused by pressure or vacuum. These tubes should never be used if scratched or otherwise damaged. Legal Information FETFE is a registered trademark of Ace Glass, Inc.