TAJIMA Utility Knife - 1 7-Point Rock Hard Snap Blade Box Cutter with Dial Lock & Rock Hard Blade - LC-650

The insulated pipe that I work with has a black plastic shell. Other utility knives wont lock the blade well and when I cut the blade pulls out of the knife. This cutter gets the job done!

Great to cut insulation, R-19 and double layer of R-13, if youre cutting R-38 you need to press the material. Overall you get precision cuts.

I have been using the Tajima knives for at least the last ten years. I install EIFS and I cut a lot of Styrofoam, and these are the best.

I do a lot of wood carving, these knives are the most durable out of any razor knife Ive ever used. I use them to aggressively take off large amounts of wood when I need, so they end up seeing quite a bit of abuse. Highly recommend these, and the blades they come with.