Holiday Lighting Outlet Shingle Tabs, Christmas Light Clips for C7 & C9, Commercial Grade, Pack of 100 Screw bulbs into sockets with clip positioned between bulb and socket Use on shingles, gutters, decks - simply wedge the legs within spaces to secure, or use with parapet clip. (Parapet Clip not included) Great for home and commercial Christmas lights installation Uses dual legs for secure mount, with a flip tab for firmer grip Holds C7 and C9 bulbs if the bulbs are replacement bulbs. Will not hold if bulbs are fixed into the cord.