Door Lock structure was to make it more stronger, family members more. locks for external/internal doors:Designed for use with door handles on internal wooden doors and also suitable for both left and right handed doors,private rooms such as bedrooms, store cupboards, and bathrooms. It is easy to install this sash lock as it only requires basic tools. All the necessary fixings are supplied for a hassle-free installation. Now upgrade your doors with this elegant latch without the need for professional assistance. It is easy to install this sash lock as it only requires basic tools. All the necessary fixings are supplied for a hassle-free installation. Now upgrade your doors with this elegant latch without the need for professional assistance. [ Suggested Use ] Suitable for internal doors with door handles, Manufacturer: ZGHQHCDRH