It looks likeChewie has a tiny monkey hiding in his mouth.
(
.Yeti. El amor en los tiempos del cólera,
Sat 20 Nov 2010, 12:55,
archived)
Thats how they got the mask to move in the film seepre-animatronics
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RedStar returneth,
Sat 20 Nov 2010, 17:56,
archived)