NexBelt EDC Belt

Do you really need a gun belt to carry inside the waistband? Yes.
Is a stiff gun belt uncomfortable? No, it's more comfortable.
NexBelt EDC Belt

Making the DeSantis Slim Tuk Slimmer

The Hellcat's engineering genius is slightly thwarted by a needlessly thick holster.
I removed the toothed mounting hardware (the top pieces in the photo) to reduce thickness of holster near muzzle.
C-clip mount point is 1/3" thinner. Positions the clip itself parallel with holster body for better presentation on belt, too.
I do have to run the retention a little tight to prevent the C-clip from swinging over to interfere with the mag release button. With the slight cant, the weight of the pistol should tend to help prevent this shift of the C-clip.
I had to ream out the C-Clip mounting holes a bit to add in a bit of can and to clear magazine release button (for left hand carry, right hand carry would not face this issue).
See my pistol reviews and my "Carrying for Self Defense" series to understand why I advocate primary left hand carry and presentation of handgun.
Magazine release button clearance is pretty close. May require grinding a bit off the C-Clip near the mag button.
Springfield Armory...paddle mag release, PLEASE.
I replaced stock screws with stainless screws I had on hand. I think they are #8-32. You could use the stock screws, the short one will just barely get an acceptable bite on the blind nut. The long screw will need about 1/4" cut off. Be sure to put a drop of Locktite on each screw.

DeSantis Slim Tuk vs Boraii Halcyon