Saw several Youtube videos for using Gutter Guards from Homedepot for air ventilation on Van/SUV door windows. Here is one video.
I bought a two with builtin screen mesh for about $2 each. Cut them down to fit rear SUV windows. Problem is the screen mesh was to big and seemed mosquitos could get through. The plastic mesh was held on with clear silicone. I had some spare plastic window screen mesh and decided to replace it with that. Cut to size and glued in with clear silicone. Turned out great. Lesson learned. Buy cheaper Gutter Guards with no mesh and install your own. Here is Homedepot meshless Gutter Guard.
https://www.homedepot.com/p/Amerima...Snap-In-Filter-Gutter-Guard-86270BX/100520851
In attached pic you can see difference in size of mesh. Also pic of finished window guard.
I bought a two with builtin screen mesh for about $2 each. Cut them down to fit rear SUV windows. Problem is the screen mesh was to big and seemed mosquitos could get through. The plastic mesh was held on with clear silicone. I had some spare plastic window screen mesh and decided to replace it with that. Cut to size and glued in with clear silicone. Turned out great. Lesson learned. Buy cheaper Gutter Guards with no mesh and install your own. Here is Homedepot meshless Gutter Guard.
https://www.homedepot.com/p/Amerima...Snap-In-Filter-Gutter-Guard-86270BX/100520851
In attached pic you can see difference in size of mesh. Also pic of finished window guard.