User opens zipper on outer jacket (video)
The user modified his outer jacket by inserting a key ring in the zipper, see related tip. He pulls down the zipper with his thumb in the key ring while holding the fabric with his teeth.
Whose idea
The user
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User opens zipper on outer jacket
Related tips

Technology to take off an outer jacket - suitable for a person with severe disabilities. 2014
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A user with extensive disabilities can use a "bite tug" to help pull up a zipper on a jacket. 2014
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The modification enables people with high tetraplegia to take off an outdoor jacket by themselves. 2014