i didn't know what it was at first...seen the three were broke off and expected the last one to break taking the hose off...got to looking at it and figured out what it did...at least i had my tool box with me this time instead of on the porch like normal...the guy at napa knew what it was as soon as i set it on the counter...he got the part before he touched the computer...said i got the last one so i'm guessing a few people have had the same thing thing happen lately