Made a simple gate latch from PETG because my gate kept blowing open in high winds. Used 5/32 lag screws. The hole and slot are 8.5 mm. It is 7 mm thick. I printed it with 100% infill for rigidity. This one faces East, into the morning Sun. It sees direct sunlight approximately half of the day.

FYI... The following weekend after I posted this, I had a heavy storm through my area. Many trees blew over, and many many limbs were blown down. At least 2 neighbors lost large limbs from trees and at least 2 gates on my street blew open. Mine did NOT, and it DEFINITELY would have before my latch addition!!!!!

Simple, but VERY effective.....

UPDATE 11/11/18: Still holding up with no problems... Winter temps have just arrived. I will update if this cracks... (Where I live, Summer temperatures rise upwards of low 100's Fahrenheit (approximately 40 Celsius), and the Winter temperatures can drop below the freezing point of water several times.)