The best way to protect your phone is to use a OnePlus 9 protective glass. Here's a great deal that's optimised to protect your screen and is made with solid quality. This case is in a hardness of 9H (9 times harder than ordinary glass)

Features of this tempered glass for OnePlus 9:

• Excellent protection against scratches and tears.
• Protects the screen from accidental knocks and drops of the phone.
• Good quality.
• Made in a discreet design with rounded corners following the shape of the phone.
• Safe 'anti-explosion' function - the protective glass will never shatter and be dangerous.
• Cleaning kit for the screen before mounting is included.
  
• The glass goes ALL the way to the edge, therefore use of a case is notrecommended

Note:ÿThe screen protector is compatible with the in-display fingerprint sensor. However, it is recommended to scan your finger and increase the sensitivity of the screen:ÿSettings -> screen -> touch sensitivity.

You greatly minimise the risk of scratches and tears to the screen when using this OnePlus 9 tempered glass, which is produced in a good quality.

Note: Fits OnePlus 9