The trapezoidal utility blades that Slice makes (that is, the 10523, 10524, 10525 series) are all compatible with our metal-handle utility knives. These knives include the 10490 Manual Metal-Handle Utility Knife and the 10491 Auto-Retractable Metal-Handle Utility Knife. Both these knives are ambidextrous and feature a large, sturdy handle. The manual version locks in place, offering three preset cutting depths, while the auto-retractable version retracts on its own, as soon as the user releases the slider.