These are three Russian (or perhaps Ukraine) emerald green glass insulators, embossed BC3 // 49, the "flat top" one has the embossing backwards. BC3 are the Cyrillic letters for VSZ, and SZ are the initials for Glass Factory (Stekolniiy Zavod). The two "triple nexk" ones may be of the CD 586 family. Note the little "bulls-eye" on the short one's dome. This may fit into the CD 568.X family. The flat top unit on the far right may be a CD 474.

[IFONA CD 586? 568.x? 586.2?]