He put his hand into his pocket and took 【out】 a small wallet .
=He put his hand into his pocket and tooka small wallet【out of】it .
take sthout：动词短语,【拿/取出】,out是副词,该短语后面不接宾语,宾语已经在两个词之间.
take sth out of sth：从.里面取出.of介词,后面需要接宾语,强调事物原来存放的地方.例如：
He took a book out.
He took a book out of his drawer.
祝你开心如意!