Wall plugs and raw bolts: how to fix into a concrete wall
To fix into a concrete wall, drill a hole with a masonry bit, tap in a plastic wall plug and drive a screw into it for light and medium loads such as shelves, curtain rails, mirrors and cabinets. For heavier fixings such as brackets, gate posts and machinery bases, use a raw bolt (an expansion anchor), and for the heaviest or most critical loads use a chemical anchor. In Nairobi in October 2026, AHIHQ Traders sells wall plugs in S6, S8 and S10 from KSh 7,975 for a carton of 100 packets, and raw bolts from M6 to M20 from KSh 10,440 a carton.
Wall fixings at a glance
| Fixing | Use it for | Sizes | Sold as | Carton price |
|---|---|---|---|---|
| Knicker wall plugs | Screws into concrete, stone, brick or block | S6 x 30mm, S8 x 36mm, S10 x 60mm | Carton of 100 packets | KSh 7,975 to KSh 9,425 |
| Raw bolts | Heavier fixings into solid concrete | M6 x 50mm to M20 | Cartons of 40 to 1,200 | KSh 10,440 to KSh 17,400 |
| Knicker bed bolts, half thread | Bolting timber through, such as bed frames | 4", 5" and 6" | Bag of 25 kg | KSh 5,800 |
| Threaded rod nuts | Nuts for threaded rod | No. 12 and No. 14 | Bags of 500 and 400 | KSh 21,750 and KSh 20,300 |
| Eye hooks, closed (No. 2) | Hanging wire, cord and light fittings | No. 2 | Carton of 200 packets | KSh 17,400 |
| Screw hooks, open (No. 2) | Hanging items you want to lift off | No. 2 | Carton of 200 packets | KSh 23,200 |
How do you match the fixing to the load and the wall?
Two questions decide the fixing: how heavy is the thing you are hanging, and what is the wall made of?
- Light loads (picture frames, small mirrors, curtain rails, light shelves): an S6 or S8 wall plug with a wood screw.
- Medium loads (kitchen wall cabinets, loaded shelves): the larger S10 plug and a longer, thicker screw, or a small raw bolt into solid concrete.
- Heavy loads (gate posts, steel brackets, handrails, machinery bases): raw bolts into solid concrete.
- Heavy or critical loads, cracked or weak masonry, or fixings close to an edge: a chemical anchor. Our guide on how to fix bolts and rebar into concrete with chemical anchors explains how.
Does the wall type matter?
Yes. Solid concrete and stone give the firmest grip for plugs and raw bolts. Brick works well if you drill into the brick, not the mortar joint. Hollow concrete blocks are harder: a plug can spin in the hollow, and a raw bolt expands into empty space, so aim for the solid parts of the block or use a chemical anchor. Ordinary plastic wall plugs are made for masonry, not gypsum board.
What do S6, S8 and S10 wall plugs mean?
The number after the S is the size of the masonry drill bit the plug is made for, in millimetres. An S6 plug goes in a 6mm hole, an S8 in an 8mm hole and an S10 in a 10mm hole. The bigger the plug, the bigger the screw it takes and the more it can hold.
| Wall plug | Drill bit | Carton | Carton price | Works out at about (per packet) |
|---|---|---|---|---|
| S6 x 30mm (200 pcs) | 6mm masonry bit | Carton of 100 packets | KSh 9,425 | KSh 94 |
| S8 x 36mm (100 pcs) | 8mm masonry bit | Carton of 100 packets | KSh 8,700 | KSh 87 |
| S10 x 60mm (50 pcs) | 10mm masonry bit | Carton of 100 packets | KSh 7,975 | KSh 80 |
How to fit a wall plug
- Mark the hole and drill with a masonry bit the same size as the plug, a little deeper than the plug is long.
- Blow or brush the dust out of the hole.
- Tap the plug in until it sits flush with the wall surface.
- Hold the item in place and drive the screw through it into the plug until it is firm. Stop before the plug starts to turn.
Raw bolt sizes and prices
A raw bolt is a bolt with a metal sleeve. As you tighten it, the sleeve expands and locks against the sides of the hole. Raw bolts are sold by M size, the thread diameter in millimetres, and the hole size is set by the sleeve, not the M number, so measure the sleeve or check the packet before you drill. Keep raw bolts away from the edges of slabs and columns, because the expanding sleeve can crack the concrete.
| Raw bolt | Carton | Carton price | Works out at about (per piece) |
|---|---|---|---|
| M6 x 50mm | Carton of 1200 | KSh 17,400 | KSh 15 |
| M8 x 60mm | Carton of 600 | KSh 11,310 | KSh 19 |
| M10 x 70mm | Carton of 360 | KSh 10,440 | KSh 29 |
| M12 x 90mm | Carton of 240 | KSh 12,180 | KSh 51 |
| M16 x 100mm | Carton of 108 | KSh 13,315 | KSh 123 |
| M20 | Carton of 40 | KSh 15,660 | KSh 392 |
When should you use a chemical anchor instead?
Choose a chemical anchor over a raw bolt when the load is heavy or safety-critical, when you must fix close to an edge, when the masonry is hollow, cracked or soft, or when you are fixing starter bars (rebar) into existing concrete. The resin fills the hole and bonds the bolt to the wall without the outward pressure of an expanding sleeve. See Chemical anchors: how to fix bolts and rebar into concrete.
Bed bolts, threaded rod nuts and hooks
Knicker bed bolts, half thread come in 4", 5" and 6" lengths and are sold by the 25 kg bag for KSh 5,800. They are used to bolt timber together through a drilled hole, as in bed frames, with a nut on the threaded end.
Threaded rod nuts come in No. 12 (KSh 21,750 for a bag of 500, which works out at about KSh 44 a piece) and No. 14 (KSh 20,300 for a bag of 400, about KSh 51 a piece). Match the nut to your rod.
Eye hooks, closed (No. 2) and screw hooks, open (No. 2) screw straight into timber, or into a wall plug in masonry. A closed eye keeps a wire or cord from slipping off; an open hook lets you lift the item off. Eye hooks are KSh 17,400 for a carton of 200 packets (about KSh 87 a packet), and screw hooks are KSh 23,200 for a carton of 200 packets (about KSh 116 a packet). We also stock metal hooks at 100 pieces a box, KSh 9,425 for a carton of 100 boxes.
Which one should you buy?
- Shelves, curtain rails and mirrors on concrete or brick: S6 or S8 wall plugs with a wood screw.
- Kitchen wall cabinets and heavier shelving: S10 wall plugs, or an M6 or M8 raw bolt into solid concrete.
- Gates, steel brackets, handrails and machinery: raw bolts M10 to M20 into solid concrete.
- Heavy, critical or near-edge fixings and rebar: a chemical anchor; read the chemical anchor guide.
- Timber bed frames and through-bolted timber: bed bolts.
- Hanging wire, cord, plants or light fittings: eye hooks or screw hooks.
Where to buy
Wall plugs, raw bolts, bed bolts, nuts and hooks are all available from AHIHQ Traders in Nairobi. You can see the full range in our fasteners and fixings collection, part of the wider tools and hardware range. These lines are sold wholesale only, by the carton or bag, never as single pieces. If you need only one or two packets, the honest advice is to share a carton with other fundis or a neighbouring site, or buy for stock. Collect from our trade counter at Royal Business Park, opposite Complast, Old Mombasa Road, Nairobi (Monday to Saturday, 8:00 to 17:30), or have it delivered anywhere in Kenya for a flat KSh 350, free on orders over KSh 15,000. We take M-Pesa or card. Contractors and shops can request a trade quote on our trade page, and you can send a list or ask a question on WhatsApp (+254 724 505 919).
Related guides
- Wood screws vs MDF screws vs gypsum screws: types, sizes and counts
- Drawer rails sizes and cabinet hardware: a fitting and buying guide
- Types of hammers and uses: claw, mason, sledge, mini and tack hammers
Common questions
What drill bit do I need for an S8 wall plug?
An 8mm masonry bit. The number after the S is the drill size in millimetres: S6 takes 6mm and S10 takes 10mm.
Raw bolt or wall plug: which is stronger?
A raw bolt in solid concrete holds far more than a plastic plug and screw. Use plugs for light and medium loads and raw bolts for heavy fixings.
Can I use wall plugs in gypsum board?
Ordinary plastic wall plugs are made for masonry. In gypsum board, screw into the stud or channel behind the board, or use a fixing made for hollow board.
Can I buy a single packet of wall plugs?
No. Wall plugs are sold by the carton of 100 packets, from KSh 7,975. If you need only a few, share a carton or buy for stock.