Rank #10 in Best Leg Extension Machine 2026: 10 Ranked, and the Capacity Claims That Don't Add Up
FNKTEK Adjustable Leg Curl and Extension Attachment
Price and rating as shown on Amazon when we collected them. Both change.
The FNKTEK Adjustable Leg Machine Leg Curl Attachment is a bolt-on leg extension and curl station for a power rack, and it takes the number 10 spot in this guide. The listing prices it at £75.99 and it carries a 5.0 rating from 6 ratings, all of them five stars. It offers 8 adjustable positions, uses two padded rollers, and the Item Highlight says it fits 50-75mm square tube power racks.
What keeps it at the bottom of this guide is what it does not claim. Where the entries above it lead with a headline capacity — 360KG, 1100LB, 660LBS — this one puts its only load figure in the smaller Item Highlight field: 175 lbs, about 79 kg, with nothing in the title to compete with that number. What it does carry is a disagreement between its own fields: the Item Highlight describes "Thickened 12cm pads", while bullet 5 says the two roller pads have a diameter of 10 cm. Every figure on this page comes from the Amazon listing and its customer reviews, not from any test we have carried out.
How those 6 ratings break down
An average hides its own shape. This is the spread behind the 5.0 stars.
Specification
Exactly as published on the Amazon listing, field for field.
| Price | £75.99 |
|---|---|
| Rating | 5.0 out of 5, from 6 ratings (all five-star) |
| Brand | FNKTEK |
| Stated max load | 175 lbs (Item Highlight; no matching figure in the title) |
| Adjustable positions | 8 |
| Pad diameter | 12 cm per the Item Highlight, 10 cm per bullet 5 |
| Rack fit | 50-75mm square tube racks; bullet 4 prints '50x50mm0x60mm=x75mm' (as listed) |
| Material and dimensions | Alloy steel, 11 kg, 63 x 33 x 16 cm |
What buyers actually say
Quoted from customer reviews on Amazon
Verified purchase“I was really excited to try this, only got delivered today and I was straight out to get this set up!Honestly the best £75 I've spent on attachments and the quality is brilliant.Solid steel frame, the rollers are really thick like gym grade quality.2 huge bolts hold it firmly in place and the weight loading pin is big enough to take 5 or 6 plates (unlike the bench attachments you normally get) so it's unlikely I'll ever max it out.Plenty options to adjust the roller spacing to suit you. The only downside is to remove it you need to remove the bolts, no quick release unfortunately so more of a permanent placement than and off and on attachment.Highly recommend this as an addition to your home gym for quad extensions and hamstring curls.”
Verified purchase“This fitted my 2018 Mirafit M100 Power Rack perfectly (26mm Bolt Size) and the build quality of this attachment is incredible for less than £100! With a little trial and error, I got the attachment fixed at the right height and the padding properly spaced for my leg length (I'm 6'3"). Whole build time took about 25 minutes including my messing about with adjustments. Couldn't be happier here! (Please note - this item does not come with any build or usability instructions, but its honestly very self-explanatory).”
What it is up against
The rivals it was ranked against in Best Leg Extension Machine 2026: 10 Ranked, and the Capacity Claims That Don't Add Up.
Questions people ask
How much weight does the FNKTEK attachment support?
The Item Highlight gives a 'max load 175 lbs', about 79 kg, for model fnk-uk-futi-shenqutui. No other field on the listing repeats or raises that figure.
Which power racks will it fit?
The Item Highlight says it fits 50-75mm square tube power racks. Bullet 4 lists hole diameters of 16mm and 8mm and prints '50x50mm0x60mm=x75mm' as listed. The review from a 2018 Mirafit M100 owner reports a 26mm bolt size worked.
How many positions does it adjust through?
Eight. The Item Highlight says '8 adjustable positions' and bullet 4 states the same number.
What is the diameter of the roller pads?
Two figures appear on the page: 'Thickened 12cm pads' in the Item Highlight, and a diameter of 10 cm in bullet 5.
Is it difficult to install?
Bullet 5 says one person can install it and that the parts are bolted together for a simple connection. The Mirafit M100 owner reports about 25 minutes including adjustments.
What comes in the box?
The specification field lists '1X Leg Extension Attachment'; bullet 5 adds that the package also includes a counterweight corner and 3x3 1 3/4 feet tubing.
Comments
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