The descriptions of the items are as follows. These wheels are made of billet 6061 aluminum right here in the USA on a precision CNC lathe center. The 2" wheels are 2" in diameter and 2 wide.
They have pressed in sealed radial ball bearings and contoured edges to aid with belt tracking (these wheels are typically used with a flat platen attachment on the belt grinder) There is a spacer between the bearing to help prevent over tightening. The 4" tracking Wheel is 4" diameter and 2.5 wide. It is crowned to help with belt tracking and it also has the spacer between the bearings to prevent over tightening.The inside diameter of all bearings used is 1/2. Make sure the Method you use to mount the wheels (I just use a 1/2 bolt with no washer and a nut on the other side) does not make contact with the inner and outer races on the bearings at the same time causing it to bind. The Drive Wheel is 6" diameter and 2.25" wide. It is crowned to help with belt tracking. This drive wheel in this listing is a 5/8 bore with a 3/16 keyway and set screw. You will receive ONE COMPLETE SET that include 6" drive wheel, 4"tracking wheel, and two 2 idler wheels. This item is in the category "Home & Garden\Tools & Workshop Equipment\Power Tool & Air Tool Accessories\Abrasives\Grinding Wheels & Cut-Off Wheels". The seller is "vwjackstraw" and is located in this country: US. This item can be shipped to United States, Canada, United Kingdom, China, Mexico, Germany, Japan, Brazil, France, Australia, Denmark, Romania, Slovakia, Bulgaria, Czech Republic, Finland, Hungary, Latvia, Lithuania, Malta, Estonia, Greece, Portugal, Cyprus, Slovenia, Sweden, Korea, South, Indonesia, Taiwan, South Africa, Thailand, Belgium, Hong Kong, Ireland, Netherlands, Poland, Spain, Italy, Austria, Bahamas, Israel, New Zealand, Philippines, Singapore, Switzerland, Norway, Saudi Arabia, United Arab Emirates, Qatar, Kuwait, Bahrain, Croatia, Republic of, Malaysia, Chile, Colombia, Costa Rica, Dominican Republic, Panama, Trinidad and Tobago, Guatemala, El Salvador, Honduras, Jamaica, Antigua and Barbuda, Aruba, Belize, Dominica, Grenada, Saint Kitts-Nevis, Saint Lucia, Montserrat, Turks and Caicos Islands, Barbados, Bangladesh, Bermuda, Brunei Darussalam, Bolivia, Ecuador, Egypt, French Guiana, Guernsey, Gibraltar, Guadeloupe, Iceland, Jersey, Jordan, Cambodia, Cayman Islands, Liechtenstein, Sri Lanka, Luxembourg, Monaco, Macau, Martinique, Maldives, Nicaragua, Oman, Peru, Pakistan, Paraguay, Reunion, Vietnam, Uruguay.