Which of the following is NOT one of the 6 main types of simple machines?

kyle.lichtenwald

clinton.brown

doran.l

fmmusharaf

a_vera

elysia.martin

ddaniel

grace.tuju

ccooper

kkelly

burnette

esraezici

brett_comerford

davidrdayii1

tfarley

marcusgoldsmith8

acraghead

mcheney

aliciaklucas