My teachers in the college very like my hobby, they like to see, somebody collect objects, which part of an old electrical industry. My teacher have been in Croatia, it is the best to have holiday on the coast. He found to me these two Insulators. The either is a 10 kV new Delta unipart with black solid-state glaze on it's head, the other is an easy double spool to 0.4 kV strain. The solid-state glaze is a very good invention, it drive the voltage distribution on the Insulator, and it protect it, and it is more expensive.. At a time I must calculate and design Insulators, it is very hard calculating and designing work..