We do not recommend buying banners with wind slits. Our 13 oz vinyl banner material is strong enough to withstand most wind events without the use of wind slits or any other type of wind resistant product.
Because wind slits create cut points in the banner material, they will actually make your banners less wind resistant! The cut in the material introduces a tear point for the banner to rip apart. The holes created by the wind slits are simply not big enough to allow enough air flow through the banner to be effective.