Dua 193 ☆
اللَّهُمَّ إِنِّي أَسْأَلُكَ خَيْرَهَا، وَخَيْرَ مَا جَبَلْتَهَا عَلَيْهِ، وَأَعُوذُ بِكَ مِنْ شَرِّهَا، وَشَرِّ مَا جَبَلْتَهَا عَلَيْهِ
Allaahumma 'innee 'as'aluka khayrahaa wa khayra majabaltahaa 'alayhi wa 'a'oothu bika min sharrihaa wa sharri maajabaltahaa 'alayhi.
When any of you marries a woman or purchases a maid-servant then let him say : O Allah, I ask You for the goodness of her and the goodness upon which You have created her, and I seek refuge in You from the evil of her and from the evil upon which You have created her.
If you purchase a camel then take hold of the top of its hump and say the same.
Reference: Abu Dawud 2/248 and Ibn Majah 1/617. See also Al-Albani, Sahih Ibn Majah 1/324.