4" plastic ball shells. (actual size is 3-3/4") ring & washer included per set. comes in 2 halfs. One half is just smooth round, the other half has a 1/4" fuse hole, perfect for our chinese fuse. Use Methylene chloride, xtlene or PVC cement to bond the 2 pieces together. All sets come with both halfs. 6 SETS
