Housing clamp?
 

I'm building up a bike and I'm at the point where I'm installing the cables and housing (by the way, I'm new to bike mechanics). One of the thing-a-ma-jiggers that the cable runs along just has a concave surface the housing is supposed to be attached to. I have two questions regarding this:

1. What do I use to attach the housing to this? Would I use a housing C-Clip, something like this: http://aebike.com/page.cfm?PageID=30...ls&sku=BR7841? I have a Bionchi that I noticed has the same thing-a-ma-jigger and it looks like there is some rubber clamp which secures the housing to it.

2. Why is this concave protrusion not just a housing guide that the housing can be threaded through? Is it because the housing is supposed to be secured at this point so that it doesn't move?

Thanks,
Nick

I'm assuming this is a mountain bike, correct? If I'm picturing what you are describing correctly, you need these (your link didn't work for me):

http://www.speedgoat.com/images/products/125587.jpg

http://www.speedgoat.com/product.asp?part=125587

The idea is, as you say, to serve as a point to anchor the housing so that it does not move. The reason for this type of feature versus a traditional cable stop is that it allows you to use a full length of housing for the cable, eliminating two areas (per stop) for water/dirt to enter the housing. The downside is that it's heavier (all that extra housing) but it's a relatively small price to pay for longer lasting housing and cables.