The tuft impact tester mounts a test probe in a suspended manner from a tripod arrangement via a gimbals mechanism so that the test probe is able to move along a vertical axis. Disclosed is a one-pack type dental adhesive composition comprising a silane coupling agent as a component, an acidic group-containing polymerizable monomer as a component, a sulfur atom-containing polymerizable monomer as a component, and other components. The memory system, as alternately configured in a second memory capacity larger than the first memory capacity, comprises second memory modules connected to the memory controller by installing the second memory modules in only the first and second connectors.