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Tower 1G Surface Box with 20mm knock out and mini knockout

Product Code: 33241

With 20mm knockout and mini knockout. Robust, heavy gauge material construction. For use with 20mm conduit systems.

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QtyPrice per item
1 - 9 £1.12
10 - 19 £1.00
20 + £0.90

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Available for deliveryNext Day Delivery
Available for collection from store Store Collection Check stock in your store
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Rated 3 out of 5 by Knock-outs can be tricky Does the job, but some of the ones I used had knock-outs that refused to budge without cutting. The back can crack if you try to knock out without cutting. 31 May 2015
Rated 4 out of 5 by Surface box 20mm knock out Used these to mount thermostats with cable glands in the knock out holes. I pushed the knockouts from the outside and they broke away cleanly. It requires a fair bit of force. Good price and fine for what I needed. 11 Dec 2014
Rated 5 out of 5 by Inexpensive and simple For those having issues reliably removing the cut-out, this approach works for me every time... Drill a central hole about the same diameter of your screwdriver, insert screwdriver, and lever to one side. The cutout should then come straight out cleanly. 3 Dec 2014
Rated 4 out of 5 by Ideal trunking to conduit box Great box for connecting 20mm plastic conduit to plastic trunking. Only gave 4* on performance because the knockout didn't work for the 20 mm hole and had to be drilled. I box was badly broken because of this so beware. 26 Dec 2012
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Brand Tower
Manufacturer Guarantee 1 years
Pack Size 1
Product Diameter 20 mm
Total Product Weight 69 kg