Coil loop insert Ferrule loop insert Flared thin slab coil loop insert Offer to sell various coil ties, different designs with different sizes for different uses, some with plastic cones. Ferrule insert Coil ties with white plastic cones, plain flat washers and plain coil rods. 1/2"x 1 3/4" coil loop insert with white plastic form work. Double flared coil loop inserts Single flared coil loop inserts