How much does this cost to the nearest dollar?

Survivor R1670 Tyvek USPS First Class Mailer, 10 x 15, White (Box of 100)
Patented release strip makes these open-end catalog envelopes easy to open. Convenient Flap-Stik closure does not require moisture to seal. First-class envelopes made of DuPont Tyvek won't rip, tear or puncture. They are much stronger and more secure than traditional paper envelopes. Water-resistant and moisture-resistant envelopes are lightweight to save on postage costs. Envelopes are easy to use. Simply peel and seal. Patented release strip makes envelopes easy to open White Tyvek envelope with Flap-Stik closure and first-class border Puncture-resistant, tear-resistant, moisture-resistant and chemical-resistant Size 10 x 15 Manufacturer 0, Brand Quality Park, Weight

Price is $51.00
Price: $50.73