To Aru Majutsu no Index Accelerator t-shirt. Available in 4 sizes.
Asian sizes are different from US and EU ones. Please measure your clothes, not your body, to choose the right size. You can find below size details (1 inch = 2.54 cm,1 cm = 0.3937 inch.):
M = length 69cm, chest 96cm, shoulder 42cm, sleeve 21cm. L = length 71cm, chest 100cm, shoulder 43cm, sleeve 22cm. XL = length 73cm, chest 104cm, shoulder 44.5cm, sleeve 23.5cm. XXL = length 76cm, chest 108cm, shoulder 46cm, sleeve 25cm.