Trampoline and Tumbling Shoes Sz 42

Trampoline Shoes are used for getting better grip on the trampoline during trampoline and tumbling practices or meets.   These are white shoes that measure 26 cm long, which coincides with a 42 size.  My son's shoe size when he wore these was a men's size 10.   The grip is nearly unused.  There are a few marks on the soles, that is just from walking in them on the gym floors. Pic makes the shoes look dingy.  The toe does have minor discoloration from walking but the shoe still looks clean.
Info about shoe material from manufacturer: Our unisex trampoline shoes are lightweight with an elastic strap across the top to ensure a secure fit. The rubber sole has a light grip to give you confidence to perform at your best. LORICO® elastic white uppers, Rubber and canvas lining.