Radar Ninja Agile Wheels 59mm x 38mm 4 Pack
Primarily used as Indoor derby wheels but I bet they would also be good in skate parks. Bargain priced. Speed grooves - the idea is that Urethane flexes and the groove gives more traction.
59mmm tall, 38mm wide
Teal 88a, Pink 91a, Blue 93a
Sold as 4 Pack