The Black Ops Sun Envy Wheelset-36H-20×1.75″ is a great upgrade to your entry level race bike or neighborhood bike.Sealed bearing Black Ops3/8″ axle Cassette hub in the rear and sealed bearing 3/8″ axle hub in the front make for a long lasting high performing wheelset at an affordable price. And with Sun Envy rims, this becomes a hard to beat combination of value and quality.