STANDARD THREAD: 1/8 IP (3/8") to 1/4-27, satisfy the harp needs. MATERIAL: High-quality brass, high hardness, strong and durable. SIZE: External thread diameter 9.6mm/0.38inch, internal thread diameter 5.16mm/0.20inch, height 8.18mm/0.32inch. APPLICATION: It can help to install the decorative cap (M10 to M6) on the top of the lamp holder on the standard harp with studs. Package includes 2pcs Lamp Holder Finial Cap Adapters. 1/8 IP (3/8") to 1/4-27 two different threads, meeting any needs of harp finial cap, allowing to decorate your desk lamp

Specification:
Type: Lamp finial cap adapter
External thread diameter :9.6mm/0.38inch
Internal thread diameter: 5.16mm/0.20inch
Height: 8.18mm/0.32inch
Material: Brass, high hardness, strong and durable.

Package includes
2pcs Lamp Holder Finial Cap Adapters