Use these envelopes for secure everyday home and business mailing. Gummed flap uses moisture to create a secure seal. Windowless, side-seam design makes these envelopes printer friendly. Quality envelopes made with smooth 24lb white wove paper. Dimensions 9.5” x 4.125” allow these envelopes to fit letter, legal or other documents and include a return envelope. Blue Summit Supplies Standard #10 Windowless Envelopes are a great choice for everyday home and business mailings. Envelope dimensions (9.5” x 4.125”) fit standard letter and legal documents, invoices, checks, and return envelopes. Strong gummed seal requires moisture but is more cost effective than self-seal envelopes. Easily print hundreds of envelopes with our low-profile envelope design that resists jamming. Our printer friendly envelopes are made from smooth 24lb white paper that works with Laser and Inkjet Printers. 500 pack of envelopes is cost effective and reduces the need to reorder.