Super material made of 95% Polyester 5%Spandex
The come with a short attached inside :)
Sizes are as follow (approximately):

S for european sizes 34-36 (45-55kg 150-165cm)

M for european sizes 36-38 (52-65kg 155-172cm)

L for european sizes 38-40 (62-75kg 160-176cm)