Check the listing for details. RAM-D-377U-4-E RAM 4" Square Post Clamp Mount with 100x100mm.... Color: Black, Condition: New. Listed at 203.99 USD. RAM 4" Square Post Clamp Mount with 100x100mm... RAM-D-377U-4-E Genuine RAM Products! hardware included (2) 5/16 INCHES -18 x 3 INCHES Machine Screws(2) 5/16 INCHES -18 Nylock Nuts(4) .312 INCHES x .187 INCHES Shoulder Washersclamp range 4 INCHES max widthsocket to socket length 11.41 INCHES hole pattern See Drawingball size D Size (2.25 INCHES )weight capacity Standard Use: 6 lbsHeavy-Duty Use: 5 lbsmaterials Marine-grade aluminumpackaging type Poly BagWeight 4.1 lb clamp range 4 INCHES max width socket to socket length 11.41 INCHES hole pattern See Drawing ball size D Size (2.25 INCHES ) weight capacity Standard Use: 6 lbsHeavy-Duty Use: 5 lbs materials Marine-grade aluminum packaging type Poly Bag Weight 4.1 lb