Sight will not allow full folding if using Kel-Tec buttstock extension.

R7 Sight Price List (prices include shipping, if ordered with a forend $5 will be refunded when order is processed):

Sight Bodies:

R7 Sight Body With Picatinny Rail $80
R7 Sight Body Without Picatinny Rail $72.50

Adapters:

Muzzlecomp Adapter With Teeth On Face $20
Muzzlecomp Adapter Plain Face $15
Non-Muzzlecomp Adapter For When Factory Metal Bushing Is Removed $9
Non-Muzzlecomp Adapter For When Factory Metal Bushing Is Left In Place $9

Useful Tools:

AR15 A2 Style Front Sight Tool (See AR15 A2 Sight Tool Page for Details) $6

The R7 is a replacement front sight for the Sub 2000 that features AR15 A2 style click adjustments for elevation and windage.
Common parts from the rear AR15 A2 sight:
Knob
Windage screw
Ball Detent Spring
Ball bearing
Flat Spring

Common parts from the front AR15 A2 sight:
Sight Post
Detent
Detent Spring

You choose your sight body and adapter combination. All sight bodies work with any adapter so any combination is possible.

Sight Body Options:
With Picatinny Rail @ 6 o'clock

Without Picatinny Rail

Adapter Options:
Muzzlecomp with Teeth Cutouts on Face (Factory Sight Metal Bushing must be Removed)

Muzzlecomp Plain face (Factory Sight Metal Bushing must be Removed)

Non-muzzlecomp (Two types available one requires Factory Sight Metal Bushing to be removed , one leaves it in place)

Features:

Bodies And Windage Insert CNC Machined From 6061 T6 And Hardcoat Anodized
Adapters CNC Machined From 1144 Stress Relieved And Parkerized
Click Adjustable Windage (same click value as AR15 M4 sights .67" @ 100yrds)
Click Adjustable Elevation (same click value as AR15 M4 sights 1.72" @ 100yrds)
Accepts Any Standard Style AR15 Sight Posts
Elevation Adjusts With Any Longer Style AR15 Sight Tool (Available On Store Page)
Windage Insert Sheilded Inside Main Body Housing
Picatinny Rail @ 6 o'clock (optional)
Muzzlecomp (optional)

Installation Instructions (Make sure gun is unloaded including magazine):
Required Tools :
1/8" Allen Wrench
Flathead Screwdriver

1.If not already done the factory front sight must be removed for install. I removed mine by cutting off the plastic sight from its metal bushing with a dremmel tool. Then if your adapter requires the metal bushing to be removed (all adapters but one does) then remove the metal bushing from the barrel. I used a heat gun set at 800 degrees and heated the bushing for about 4 minutes at which time the bushing easily slid off and the residue from the loctite that held the bushing on could be wiped clean .
Some have used a flame directed on the metal bushing (not the barrel as to not discolor it).

2.Slide adapter onto the gun (non-muzzlecomp adapters go longer solid circumference end first) and all the way against barrel step shoulder or in the case of the non-muzzlecomp adapter that allows the factory sight metal bushing to be left in place slide till it bottoms out on metal bushing (lip in adapter ID).

3.Orient so that the longitude (parallel to the barrel) milled slot is at 6 o'clock on the barrel.
Place the sight body over the adapter and orient so that the radial milled slots are evenly revealed in front of and behind of sight body (This should place your sight in the right position length wise on the barrel for folding and locking). Snug clamping screws till everything is snug but can still be moved around.

4.To get your sight lined up close so less drastic windage adjustments will be needed its best to have a red dot sight mounted to line it up with and then tighten clamping screws to 6 ft/lbs. Lining up with a laser bore sighter should work as well. If not using these eyeballing should be fine, if off more than you want to compensate with windage just reset.