Cold insulation and heat insulation OK. Stainless vacuum bottle that lightly, small, and doesn't crack. It is easy to maintain the inside because it is a caliber of [hirokuchi] that the hand enters easily.
The hot summer decreases the frequency that opens an icebox and becomes conservation of energy.

Note: You may be able to successfully guess the basic meaning of this text if you read it in an indulgent and open frame of mind. The meaning cannot, however, be grasped instantly. There are many translation errors.

Capable of hot and cold storage! Light, small and unbreakable stainless steel thermos bottle. Because of its wide caliber that lets you insert your hand, you can easily wash inside.
Using this thermos bottle, you save electricity by reducing the number of times you open the refrigerator.

Note: This is a direct translation with redundant expressions but all of the Japanese information is included. No grammatical errors.

OK for cold storage and hot storage! This is a light, small, unbreakable stainless steel thermos flask. It has a wide mouth, for easier cleaning inside.
It saves electricity during hot summers by reducing the number of times you open the refrigerator.

Note: Frequently-used natural-sounding expressions are selected instead of dictionary definitions.
E.g. 1: thermos bottle → thermos flask
E.g. 2: wide caliber → wide mouth
Readability is better than one of Casual translation.

Effective for both hot and cold storage, this thermos flask is light, compact and shock resistant, with a wide mouth for easy cleaning inside.
Saves you power, too, by reducing the number of times you open the refrigerator during the heat of summer.

ポイント：もはや翻訳のにおいがしない。アピール力のあるコンパクトで読みやすい表現。