SLR 106FR Question

Could you guys please help me out with my Arsenal SLR 106FR AK. I bought it with an Ultimak rail installed. The rail has vent holes. I want to take the rail off and replace it with the original furniture and parts. I am planning on buying them from K-var.

The question is, what tube do I buy? One with or without vent holes?

Thanks,
AF

Without.

Thanks for the quick reply.

AF