BoundBox™ Letter Check

1/4" Mail Thickness Gauge

Stop guessing and start shipping with confidence. The BoundBox™ Letter Check is designed to instantly verify whether your mail qualifies for USPS letter rates by confirming it stays under the critical 1/4" thickness limit.

Simply slide your envelope or mail piece into the slot — if it fits, you’re good to go. No more returned mail, no more overpaying for postage, and no more second-guessing at the post office.

Built specifically for resellers, card sellers, and anyone using USPS letter shipping, this tool saves time and money on every order.

Features

• Confirms USPS 1/4" thickness compliance

• Fast, simple pass/fail check

• Clearly marked for easy use

• Compact design for any packing station

• 3D printed for durability

• Designed to integrate with the Bound Box™ system

Perfect For

• Trading card sellers

• eBay standard envelope users

• Resellers

• Small business shippers

• Anyone mailing flat items

Important

This tool is for measurement verification only.
Always follow current USPS guidelines.

Why You’ll Love It

• Prevents returned mail

• Avoids postage upgrades

• Saves money every month

• Speeds up your workflow