New Turnbuckle. 

Total Length ~6", Center to Center ~5.375", aluminum hex bar is 4" long.  Rod ends are 10/32, one rod is RH thread, the other is LH thread, so it provides true turnbuckle functionality.

This turnbuckle is commonly used with the dual carb linkage kits.  Please make sure the length is correct for you.  No returns, no refunds.

See other listings for other sizes: 

7":  7" Turnbuckle for Enderle dual carb Linkage kit supercharger 6-71 blower | eBay
5": 5" Turnbuckle for Enderle dual carb Linkage kit supercharger 6-71 blower | eBay

4.75" or 4.25": Turnbuckle Linkage Barrel Valve Enderle Birdcatcher Bug BAU-3 Injector blower | eBay

Other auctions for Linkage Parts include:  Shaft Collars, Arms, Turnbuckles, Main shaft, anchor blocks with Heims, Blower Main Base plate, Main stand w/ short shaft and bearing.

Littlefield, mooneyham, rcd, holley, weiand, quick fuel, aeromotive, demon, bds, rcd, 6-71, 8-71, 10-71, 12-71, 14-71