4-1/8" Focal Point Quick Clip Outside Corner Connector Block, Allow Miter Free Cuts For Crown Moulding, They Install Easily Between 2 Pieces Of Crown Moulding To Eliminate Any Cutting Making The Installation Very Easy, To Install, Simply Fasten Blocks & Connectors To Wall Then Cut Moulding At A 90 Degree Angle, 1/4" Longer Than Space, Apply A Bead Of Adhesive On The Back Of Moulding & Snap Moulding Into Place Between Corner And/Or Connector Blocks, Secure Moulding To The Wall With Nails Or Screws.