Armorsuit makes a screen protector for the Series 4 watch. The sell on Amazon.couldn't find any screen protector for the new 44mm model on Amazon yet
ArmorSuit Apple Watch Series 4 Screen Protector (44mm)(2 Pack) MilitaryShield https://www.amazon.com/dp/B07HCNHYGW/ref=cm_sw_r_cp_api_bQLSBbRDWFBY5
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