Use the Commercial Door Thumb Turn Opening Tool to unlock a commercial storefront door from the inside. This door opener tool is inserted between the crack where the door meets the jam. Poistion the U-shaped tip so that it straddles the thumbturn and rotate the bottom handle to rotate the thumbturn and retract the bolt. Requires a gap of about 13/64" to insert tool. This will not work on all commercial storefront doors as the shaft may be too thick to fit through the crack in some door applications.