Specification Brand : Service Caster BulletPoint1 : These Service Caster Series #20 Hard Rubber casters offer various wheel sizes and mounting heights: 3” Wheel: 4-1/8” mounting height; 3-1/2” wheel: 4-5/8” mounting height; 4” wheel: 5-1/8” mounting height; 5” wheel: 6-1/8” mounting height. BulletPoint2 : Weight Capacity: 3": 275 lbs Capacity/Caster; 3.5": 285 lbs Capacity/Caster; 4" and 5": 300 lbs Capacity/Caster BulletPoint3 : All casters feature a 12mm diameter (1.75 TPI x 1-1/2”) threaded stem. Threaded stems can be difficult to measure. Service Caster recommends having existing threads checked on a thread gauge to determine correct thread size before ordering. Don't see the size you need? No problem! Call us or message us by clicking the blue Service Caster Corporation hyperlink underneath the buy or add to cart button and then clicking the ask a question button. BulletPoint4 : Brake options include a top lock brake (TLB) or a total lock brake (TTL). The top lock brake (TLB) places a positive locking force against the wheel tread locking the wheel only. The total lock brake (TTL) also places a positive locking force against the wheel tread, but the total lock brake (TTL) simultaneously locks the wheel and the swivel for a complete stationary position. BulletPoint5 : Find other wheel materials, sizes and all Service Caster products at our Amazon Storefront. Click on the “by Service Caster” link above the main title on any Service Caster page listing. Color : 4 Swivel w/2 Top Lock Brakes ExternallyAssignedProductIdentifier1 : 0020418175794 ExternallyAssignedProductIdentifier2 : 020418175794 ItemName : Campbell Chain Tie Down Chain 5/16 X 20' 4700 Lb ItemPackageQuantity : 3 ItemTypeKeyword : coil-chains LoadCapacity : 300.0 pounds Manufacturer : KD Tools Material : Hard Rubber ModelNumber : Series #20 NumberOfItems : 4 PartNumber : 513578 ProductDescription : Campbell Chain Tie Down Chain 5/16" X 20' 4700 Lb ProductSiteLaunchDate : 2015-06-10T00:34:50.511Z Size : 5" Wheel SupplierDeclaredDgHzRegulation : not_applicable UnitCount : 4 UnspscCode : 31160000 WebsiteShippingWeight : 7.7 pounds