Draper-35880-Petrol-Compression-Tester-Draper-35880-Compatible-with-direct-&-indirect-petrol-engines-which-use-14-&-18mm-spark-plug-threads-The-dual-reading-pressure-gauge-0-300psi-0-20bar-is-fitted-with-a-heavy-duty-rubber-protector-Fitted-with-a-spring-loaded-pressure-relief-valve-&-integrated-Schrader-one-way-valve-system-Supplied-in-a-plastic-storage-case-br-Draper-35880-Petrol-Compression-Tester