door chain

Noun

 * 1) A device that allows a door to be partially opened from the inside, whilst preventing it from being fully opened from the outside

Translations

 * Chinese:
 * Mandarin: 門鏈
 * Finnish: oviketju
 * French: chaîne de sûreté, chaîne de porte
 * German: ,
 * Japanese: ドアチェーン
 * Russian:
 * Spanish: cadena de puerta