Differences between normal slider and angle slider

Could someone explain me whats difference between normal slider 0º and angle slider?

Thanks

Are you talking about rear leaf spring sliders?

The only angle sliders I've seen are made by CalTracs. I think it could be an issue of re-inventing the mousetrap. They may have figured they'd be a good addition to their product line but would need a change of some sort as a sales feature. I sure can't see much of an advantage. Certainly not at twice the price of the ones from Speedway Motors !!!