KD-271SMZ… Steel Corner Connectors Set of 4. Corner L Plate is 3-1/2 Inches Long by 1-1/2 Inches Wide. Flat Plate is 1-1/4 x 3-1/2 Inches. One bolt on each L corner connects to flat plate, all other holes are for attachment to you project. One bolt is included with each corner but attachment screws are not as we don’t know which screw lengths each customer needs. Super Rigid Corner Joiner, for bed rail fastening, partitions, platform bed frames, platform bases, 4 sided booths etc. or any project where 4 sides need joining. Top and bottom tabs on male section provide lateral rigidity. Incorporated 5/16″ captive bolt provides quick fastening. Good bed rail fastener. Heavy corner gussets maintain angular integrity. .072 guage cold-rolled steel, zinc plated.