A better miter bar?

Miter Bars & Kits miter slot bar Mitre bar 450mm or 300mm for you to choose 1 x Miter Bar Slider Material: aluminum alloy Extruded aluminum and hard anodized for miter slot track The screws in the UHMW were counter sunk with flat bottom drill bit BUT during all that I noticed that a 34 scrap of MDF fit the miter slot

miter slot Material: Aluminum Size: 200MM Can be attached to 30mm45mm miter tracks Allows you to create a wide variety of jigs Cannot be attached to 19mm