McClain Frame To Crossbar Support Used With The 4 1/2″ And 5 1/2″ Tall I Beam. SKU: 2332 Category: Crossmembers **Works With Aluminum I Beam Trailers** Related products 3″ X 3″ Straight Crossmember Aluminum Over 58″ Call For Price Part #:1184 Any Crossmember Over 58" Long. 7 1/2″ Aluminum I Beam Call For Price Part #:218 Sold By The Foot. 12″ Poly Keel Pad Call For Price Part #:1193 Fits 3" Wide Crossmembers. 8″ Aluminum I Beam Call For Price Part #:219 Sold By The Foot.