Grip For Panasonic Lumix GX85 GX80

Will it fit to Panasonic GX9?. How much grip weighs?. Grip with nut and screw weighs 40 grams (1.4 ounces) vs. 130 grams (4.5 ounces) of official DMW-HGR2 grip. The hand grip is printed by 3D printer.

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