Metal locking latches are the best option for most tool boxes.
Brad's Deals Editor David,
Get this DEWALT Tough System Tool Box for $26 at HomeDepot.com. Shipping is free over $45 or you can choose free in-store pickup to avoid shipping fees. This was the best price we found by at least $11. It has metal locking latches, internal cups and lid storage compartments, and is water sealed and rust resistant. Sales tax is charged in most states.