Have 450 (I counted) #10 white security envelopes with left window for sale. They have a gummed seal for closure, #10 are considered the “classic” envelope for businesses in the US and it was what we used at my former business, which is what these are left over from. The envelopes are 9.5 inches by 4 (1/8) inches with the window being 4.5 inches by 1 (1/8) inches. They are security envelopes in the fact that the address is put behind the window and not hand-written (or typed) on the front. Asking $25 or best offer for box of 450 envelopes. Local pickup is available if close enough, otherwise shipping is available.