I have had a few of these before, I guess these are radio antenna insulators. Anyhow,2 are glass and 2 are cobalt porcelain of varying size. All are in VVNM cond, maybe a couple of marks here n there. On the small one there are 2 small rib slivers (seen in pic) $6.50 + $4.50 shipping in USA for all 4. PRICES HAVE BEEN SLASHED TODAY TO MOVE ON ALL MY OTHER OLDER LISTINGS!