The necklace fasteners are 2 part clasps - press the tab down to release (See 2nd photo). Each clasp has 2 holes, so brilliant for multi-strand necklaces. Made with brass coated in gold, therefore lead and nickel free.
The clasps are 16mm long by 14mm wide & 4mm deep. Holes are a 1-2mm in diameter.
I am a UK seller and provide cheaper postage to UK customers. 85p for the first item and 10p for anything else in the same order for listings that starts with "UK Seller. Cheap Postage". If not calculated automatically I will always refund any excess postage.