Here are our recommendations for sizes for each our categories:
ATV - Off-roading Whip Flags:
12x18 Double Sided - 4x Stitching and Tight Corner Cross stitch ( most popular)
2x3 ft Single Sided or Double Sided with 6x Stitching Tight Corner Cross Stitch
3x5 Single Sided 4x Stitching and Tight Corner Cross stitch ( We do not recommend Double Sided 3x5 for vehicle use. It's too heavy)
Boat & Nautical:
We recommend all sizes for boating flags. However be sure to add extra stitching when going double sided. We don't recommend 3x5 Double Sided for high wind high speed situations.
Motorcycles:
6x9, 9x12, 10x15, or 12x18 inch is recommended. Please note that we make all motorcycle flags sleeves to fit the standard 3/8s inch pole for motorcycles. If you need another size sleeve you must let us know in the design notes.
Cheer / Festival Flags:
Any size will do. Please note that the telescopic poles we sell will only support max a 3x5 foot SINGLE SIDED flag. Double sided 3x5 is too heavy and will require a more substantial non telescopic fiberglass pole.
Highway use / Pick up Truck Flags:
We do not make flags specifically for highway use so we cannot not recommend any size for pickup truck use but if you insist, the smaller the better and always single sided if you want it to hold up longer. The best we can do is max stich these but please be aware that you are subjecting your flag to "hurricane like" winds so we do not guarantee any durability for flags used on pick ups and you are using at your own risk. Please also be aware of the laws in your state.