Please note: Although the instruction manual is shown in the product images, it is missing. Please be aware of this. I have used it several times. There are dents in the knee mat. There is no outer box. Your abdominal muscles will be quite sore. It will be shipped in a recycled cardboard box of an appropriate size. To reduce shipping costs, it will be shipped via Eco-Mercari. Please purchase only if you agree with the shipping method. [2-in-1 Design & Armrests] Using the ab wheel, you can not only get ripped abs, but also easily do planks, allowing you to train your entire body thoroughly. In addition, the armrests support the body and increase stability, reducing the burden on the arms and shoulders. [Auto-Return Function, Further Improving Efficiency] The auto-return design allows even beginners to exercise with ease. The auto-return feature makes it easier to use for beginners, and it also increases enjoyment and is expected to increase motivation to continue. It also has a smartphone holder and timer function. By watching videos and exercise data, you can adjust the amount and speed of your training, thereby enhancing the exercise effect. [10cm Wide Two-Wheel Design, High Stability] The ab training equipment has a 10cm*2 two-wheel design, which provides excellent stability during training and helps to improve body balance. In addition, the knee protection mat and non-slip handle enhance safety and comfort, allowing you to concentrate more on training and leading to training effectiveness. [Easy Assembly & Easy to Carry] The ab wheel, which can be easily and smoothly assembled in a short time even by beginners, does not take up space for storage, does not damage the floor, and does not make noise, so you can use it with peace of mind at home. You can put it in your bag and carry it wherever you want to go, and you can take it out and start training anytime. [Training Frequency & Support] For beginners, training 3 days a week is appropriate. It is recommended to take a 1-minute break between sets and aim for 3 sets of 10 repetitions. Please adjust the training frequency and time to suit your convenience. Also, it is normal to experience slight muscle soreness the day after exercising. Size...FREE SIZE