The Gridfinity holder for a Heatgun - e.g. the one you can buy on Aliexpress: https://www.aliexpress.com/item/1005005239400615.html

Consists of two parts. Manage the tolerances carefully - I haven't added any so if you keep the outer border precise - you'll be good.

If you need it in one piece - ping me, I'll create it in one piece - it's quite long to be fit in a typical most popular 3d printer bed so I don't think anyone would need it - but in case that's the case - as I said, ping me in the comments.

P.S. do I care if You use it for smth commercial - absolutely not, do with it whatever you want :)