Luggage weight limit is everywhere around the world. As passengers often worry about over-weight, they find no way to know the weight in advance.Most people try to “feel” how heavy their luggage is by handling them by hand. “20kg weight limit”uses such habit of handling luggage by hand and adds in “Force Spring Balance” on handles of luggage to measure the weight. When users lift the luggage, the weight of luggage transforms the shape and size of spring. Users are able to know easily if their luggage is overweight from the color on luggage’s handles. If luggage is over 20 kg, the color on handles is red as a warning of over-weight. If not, the color would be green.

世界各國都有行李運載重量的限制，旅客時常擔心行李超重的狀況，卻無從得知行李重量。大多數的人通常都會以提行李的行為感覺看看行李的重量。「20kg weight limit」利用使用者提握行李重量的習慣，在行李的把手上加入了“拉力彈簧秤”的結構方式秤重，當使用者將行李向上提起，行李的重量會透過彈簧變形大小，使用者可以輕易從把手上顏色的顯示直接了解是否超重。當行李超過20公斤，使用者在提行李的時候把手會顯現紅色，警告行李過重。若是行李沒超重則是顯現綠色，告知使用者行李並沒有超重。