Compatibility: R5/R9/R12/R16/R21

For applications with R9, R12, R16 and R21 bases: This adapter allows you to securely attach the base to the three holes of the bracket for greater stability.

For applications with R5 base: Converts 2 holes into 4 holes for a more secure hold on the bracket for greater stability.

Made of durable steel material, ensuring sturdiness and durability.