They are pricey because its oil resistant silicone. Well thye say it is so hopefully they are selling you oil resistant silicone. Normal silicone will deteriorate faster than rubber when it see's oil. I silicone at work, so I see this all the time.
Those hose clamps in the pic above Eric too will chew out the silicone hose, lined clamps is what should be used....
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i used these for reducers...
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