there are certain products that can't be tested before you use them because they can only be used once and then become useless or need re-setting.
example... a match.
OK, you can test a random match from a box of matches but you cant actually test an individual match to make sure it works and then use it again later.
another... a ring pull on a can of pop !!!
how many more are there ???
example... a match.
OK, you can test a random match from a box of matches but you cant actually test an individual match to make sure it works and then use it again later.
another... a ring pull on a can of pop !!!
how many more are there ???