Zinc Plated Sliding Rectangular T-Nuts For T-Track Fixtures

Metal made, Zinc plated. T-Tracks - Mitre Tracks - Fixtures Accessories - Sliding Rectangular T-Nut.Sold in packs of 10.
(STS1) 1/4" x 20TPI width 12.7mm 

(STS1A) 1/4" x 20TPI width 11mm 

(STS2) 5/16" x 18TPI 

(STS3) 3/8" x 16TPI