Cold-formed steel (CFS) studs: C-channel profile, 3-5/8 x 1-5/8 in, 20 gauge (33 mil). ASTM A1003 G60/G90 galvanized. Non-bearing interior: 25 gauge at 24 in o.c. Bearing exterior: 20 gauge (or 18/16) at 16 in o.c. per AISI S240. Track: top and bottom, same gauge. Advantages: non-combustible (required in Type I/II buildings), dimensionally stable (no warping/shrinking), lightweight, termite-proof, 100% recyclable. Connection: self-drilling screws (#8 or #10), clinch, or weld. Disadvantages: thermal bridging (ci required for exterior), cutting tool noise, limited load-path familiarity among some crews. CSI 05 41 00. Cost: $0.40-$0.80/lf ($3-$6/sf wall installed). Used in: commercial, multifamily (Type IA/IB/IIA buildings).