Description APT STB-150 Secondary Test Boot for XP-150-SC pipe made using fuel-resistant nitrile rubber. Employ brass air chucks and stainless steel clamps for maximum corrosion resistance. APT secondary test boots are designed for testing the integrity of secondary contained flexible piping when using APT clamshell fittings. Each boot has an air chuck for applying air pressure to the secondary containment jacket. Placing a boot on each end of the secondary containment jacket forms an airtight chamber for testing. After the testing is completed, slide the boots back on the pipe to open the secondary system. The boots remain on the pipe available for future testing as required by local regulations.