Convert raw-edged holes to smooth, neat, insulated holes. Insulate and mechanically protect electrical and telecommunications cables, tubing, hose, rope, and utility lines. Locking fingers snap into holes with fingertip pressure. Locking fingers in fractional increments up to the maximum panel thickness. Withstand a push back force of 35 pounds. Available in multiple sizes for use in .250" (6,4 mm) to 6.00" (152,4 mm) diameter holes. We offer the following brass-colored parts for lamp and lighting applications: Part No. 2012, SB 312-3 Brass Part No. 2033, SB 375-4 Brass Part No. 2041, SB 437-4 Brass