There is no default password. You do not require to use password to connect with Samsung HM1350.
Yes, this is 100% original Samsung product.
Just 10.8 grams.
Yes, you can mute the ongoing call also.
To connect Samsung HM1350 with your smartphone, please follow the below steps.
01) Make sure that your smartphone's Bluetooth is switched ON.
02) Switch ON your Samsung HM1350
03) Now search for the visible devices on your smartphone
04) select Samsung HM1350
and you're done.