These Revgear shin guards are extremely light, without compromising the quality of protection.$12
are these the Revgear Youth Shin Guards? http://www.revgear.com/product/youth-shin-guard/
These are the standard revgear adult shin guards with the Revgear youth branding.
Would these be a good choice for Muay Thai?
Pair, right?
Yes, it's a pair.
Measurements for the different sizes?
Mediums are approximately 13.5" (shin portion) and 6" (instep portion). Larges are approximately 14" (shin portion) and 6.5" (instep portion).