As the industry leader, Kwikset has provided trusted security for over 70 years and has become synonymous with security, peace of mind, style, and innovation. The largest-selling deadbolt in America, the 600 series provides tough, effective protection at an affordable price. This double-cylinder deadbolt is operated by a key on both sides. The complementary Antique Brass finish offers a warm feel with deep accents in the contours of the product.