So, what you;re saying is:
Go to an autoparts store, ask the guy or girl behind the counter what you should buy.
If you can't figure out how to replace the blades in 15 seconds out in the parking lot (or you don't want to mess up your new manicure), get the guy or girl behind the counter to do it for you.
Thanks Mom. Are we having meatloaf or pot roast tonight?