When looking at buying a heavy duty Lunchbox you will need a thermos that keeps your hot liquids hot for up to 7 hours and cold liquids cool for at least 9 hours.Here are some heavy duty lunch boxes that have stood the test of time;the Stanley models have been around for generations,so have the Bento brand,these are the top two thermos lunch box brands.Thermos lunchboxes are available to fit into just about every budget.Consider your budget carefully and be realistic only buy what you can afford!They are not an investment they are a lunchbox that is to be used,so budget accordingly.The Stanley 20oz is leak-proof food jar will keep your chili or soup warm all day.Featuring an extra sturdy build it'll keep your food intact until you're ready to dig in.I bought both the Stanley 20oz Bolt Vacuum Food Jar and the Stanley Heat Saver and after using both.I would strongly recommend the 20oz Bolt Vacuum Food Jar over the Stanley Heat Saver food Jar Hands down.The 20oz food bolt hold heat way longer and you won't be disappointed like you will be if you buy the Heat Saver food jars.Whether in the office or on the go,you can take a healthier,tastier,more interesting lunch with you thanks to Mr.Bento Stainless Lunch Jar.One of the most versatile lunch boxes you'll ever come across,the Mr. Bento lunch jar comes with four different containers that allow you to pack a multi-course lunch of both hot and cold items easily and securely.

In fact,there many types of containers,they made of vacuum-insulated,stainless steel and also plastic.Now plastic boxes are applied widely,but its production of materials of concern.PET plastic can solve the problem.But What does PET stand for?PET stands for PolyEthylene Terephthalate and is sometimes referred to as PETE,PETP,or PET-P.PET is a thermoplastic polymer in the polyester family that is formed by combining two types of monomers together;ethylene glycol and purified terephthalic acid.PET plastic is naturally colorless and highly transparent.PET plastic is strong,lightweight,shatterproof,and has excellent barrier to gas,alcohol,and other solvents.PET plastic is relatively inexpensive to manufacturer and is highly recyclable.The clear plastic boxes made of PET plastic can withstand high temperatures and it’s cheap and useful.The large soup bowl comes with gasket-sealed lid to prevent messy spills and is specially insulated to keep soup hot.All pieces should be washed by hand with non-abrasive cleaning pads.Inner bowls are microwave-safe.A spork with its own protective cover attaches to the Mr. Bento lunch jar,and the jar itself has its own lid with lock and comes in a zippered carry bag with a strap for easy transport.

The bento thermos heavy duty lunch boxes are very versatile,unique and functional.This lunch box is made with a stainless steel construction and vacuum insulation.This thermos has four microwaveable inner bowls,washable container and also a convenient carry strap for easy transport and an easy to carry bag.These are just two very popular heavy duty lunch boxes,but health cheapest Clear Plastic Boxes have gradually replaced them.

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