Ultra Precision Manufacturing: Di Hed Yokes (DHY) Manufacturing facilities are a specialty of APPRO Development, Inc., a general contractor with more than 25 years of commercial building construction. In 1997, APPRO Development completed the construction of a 52,000 sq. ft. “Ultra-Precision” manufacturing facility for Di Hed Yokes (DHY).  This facility consists of 2 stories and includes approximately 12,000 SF of …