Sobres de seguridad tintados autosellables n.° 6 3/4 - Sin ventana, tamaño 3-5/8 x 6-1/2 pulgadas - Blancos - 24 lb - 300 unidades (34300)

I've used thousands of these envelopes (this brand) over the years and I can say they are the best around and at a really good price. Also the number 9 and 10 double window are awesome.

Smooth sailing, the size that I ordered...