What does this groove in my new lifters do?

[robk46]

Got the Edelbrock 5487 kit,and the lifters have a small groove around the bottom of the lifter. I've never seen this before. . .What does it do?

Picture's a little fuzzy, but you get the idea. . . The Edelbrock part number for the lifter is 9749.

 

[86 TR]

Those lifters look like GM lifters. If I remember correctly. The groove doesn't do anything.

 

[TurboBob]

Real OEM lifters are made from 2 different materials. The groove is where the 2 parts are joined.

Bob