Screw-lock Biothane® cuffs

Our screw-lock Biothane® cuffs are the perfect addition for someone who wants an always-available restraint to keep them in check, or likes having a reminder of their ownership around their body that they can’t remove without permission. Made of genuine Biothane® strapping, solid ABS clasps and locking with an unusual stainless steel security screw.

These screws aren’t ones you’ll usually find bits for in your standard security screw bit case, so we’ll send you a tool for applying and removing your cuffs too! If you later want to wear them permanently, good news! We also make pins that replace the screws to make them permanent!

Compatible with our cute faceplates, plus we can add an extra personal touch just for you with custom vinyl lettering!

These cuffs are waterproof and suitable for everyday wear.

What is Biothane®?

Biothane® is a substitute to leather, commonly used in high-end horse-riding accessories and dog harnesses. It’s extremely strong, tough and durable against the elements, and unlike leather does not soak and degrade in water after a long time. It’s available in dozens of colours, from dark leather-like browns to vibrant neons, so we’ll probably have a shade you like the look of.

Getting your measurements

To measure your cuffs, you’ll need a simple tape measure. We take measurements in centimetres (cm). Place the tape measure on your wrist or ankle where you’d like to wear your cuff and hold it gently against the skin, overlapping the ends and add length until you find it most comfortable. We’ll add the slack needed for our clasps, and will make your cuffs to within a few millimetres of the measurement you provide (plus that slack), so take a little time to find what feels best for you. For comfort, we recommend wearing your cuffs slightly closer to your torso than your wrist or ankle bones. Unless you want a particularly tight cuff, don’t pull the tape measure tight when measuring. Everyone’s body is different, but in general, we find that ankle cuffs should be worn looser (to allow all those tendons and muscles to move about), whereas wrist cuffs can be more snug. We also recommend making sure both your wrists/ankles are the same size, just in case!

Keep in mind that your cuffs shouldn’t slip off your limbs! This is very easy to achieve with ankle cuffs, but for wrist cuffs, you may be able to slip out if they’re too loose. To test this, pinch your tape measure at the dimensions you’d like your cuffs to be and see if you can pull it over your wrist and hand. If you can, or nearly can, consider going a bit tighter.

Full measurement information for our restraints

D-rings

By default, our cuffs are a simple, interlocking clasp and an unbroken Biothane® band, resulting in a beautiful clean aesthetic. Our new clasp designs as of October 2025 integrate D-rings into the clasp itself, improving on our previous offerings. Our standard cuffs come with welded 304 stainless steel D rings that are 20mm across and 3mm thick, which are extremely resistant to corrosion and are very hard-wearing. If you’d like less metal on your cuffs, you can opt for nylon plastic D-rings, or forego them entirely! If you fancy a more chunky option for your ring, we offer several other options, including 4.5mm thick black, rainbow and golden finished zinc. These are also very tough, but they will show their age more quickly with very heavy use.

Taking care of your cuffs

Our cuffs are waterproof and will not rust or tarnish in freshwater or saltwater. We use Biothane® and brass eyelets for the main cuff bands, and ABS plastic for the locking clasps, that are vapour smoothed to make them more comfortable, easy to clean and glossy. If your cuffs get dirty, you can clean them with any body-safe soap and water, and you can safely wear them in the bath or shower and while swimming. Biothane® is highly resistant against UV damage, but if you’re storing them for a long time, please put them somewhere out of direct sunlight.

Both parts of our cuffs are damaged by certain solvents, particularly acetone, used in nail polish remover. If you do spill exotic substances on your cuffs, just wash them off with water.

We use brass threaded inserts to catch the screws, and brass eyelets on the Biothane® band, which may slightly tarnish after a long time in saltwater or chlorine-treated water, so if you’re spending days at sea or at the pool, just have a shower afterwards. Our screws and standard D-rings are made from 304 alloy stainless steel, and are impervious to basically everything your skin will touch.

These cuffs are designed for everyday comfort, to be a reminder of your place and to be a statement piece. You can effectively use them as restraints, but they’re not suitable for extreme weight-bearing such as suspension. Please experiment with your cuffs before fucking them up. Our clasps are designed to break at the clasp under extreme stress for safety, and the Biothane® band will not usually be damaged. However, for use in your day-to-day life, to keep you where you should be and for in the bedroom, they’ll hold up!

We’re pretty new to this, and we want to improve our cuffs as we go, so if your cuffs fail at the clasp within the first year outside of rough play, please let us know – we’ll send you some free clasps if you let us know how it failed and sent us photos.

Picking your band colour

The colour options listed here on this page show the colours as advertised by our main supplier.We now offer both standard colours and a selection of colours retro-reflective bands across the length! Think safety jacket reflective stripes. We know some of you really like these.

If you would like to see how a certain colour looks in particular lighting etc, please get in touch! Certain colours also fluoresce (appear to glow brightly) under deep blue and ultraviolet (UV/blacklight) light, including all neon options, and a few others. If you’d like to know whether a certain colour is fluorescent, get in touch!

Custom colours

We can provide our cuffs in any colour we can get our hands on. For our main bands, we offer dozens of colours, and if you find another colour you like more that’s available in 19mm Biothane® BETA, we’ll source it for you if we can. We make our locking clasps from printed ABS plastic that’s then surface treated to bring it to a lovely smooth surface with a shiny gloss. We’ll happily manufacture your clasps in any colours we can source, and can also optionally apply body-safe finishes such as ceramic coatings and paints/clear-coats. If you would like surface finishes added to your cuffs, please contact us before ordering as we’ll have some material science to do in the paint shop.

Adding text or icons to your cuffs

If you’d like to add an extra touch of personalisation to your cuffs, we’ll happily apply vinyl lettering or symbols just for you! Whatever your heart desires, if we can apply it (and it’s not too intricate as to where it wouldn’t be strong enough), we’ll do our best to make it happen. We can provide vinyl in dozens of colours, including solid tones, pastels, gloss and matte, reflective, holographic, glittered and plenty more. If you’d like to add an extra touch of you to your restraints, add our vinyl printing to your order. It’s surprisingly cheap!

If you want something customised beyond the options we offer here, please get in touch!

Shipping

For customers in the UK, we ship all orders using Royal Mail, with the option for fully tracked services. For international customers, we offer both Royal Mail International Tracked services, and for certain countries, UPS courier delivery. Due to new rules from the US Customs and Border Patrol agency, we need to collect 10% import tariffs at checkout, but we pay these to US CBP so you have no extra import fees to pay when they arrive in the US.

Manufacturing time

We expect to ship cuffs at most 4 weeks after you place your order, but possibly much faster, depending on your specifications. Certain colours of Biothane® which are either in very high or low demand, or colours you’re the first to request, may need to be ordered to fulfil your order, but we place materials orders regularly and materials usually get to us within a week at the most. If we’re waiting for materials for your cuffs, we’ll send you an email. If you request a customised item, materials and tools may take longer to get to us, but we’ll update you personally if this is the case.

Legal notice

Designs for the locking clasps may change slightly between the photos shown and manufacture due to improvements in design. Although we use 3D printing to manufacture the clasps for these cuffs, we work and finish them extensively by hand, and all other parts are made by hand, so small imperfections may be visible, especially on lighter-coloured printed parts. These products are sold as toys suitable for adults only, and should not be used without appropriate experience. They should not be used as part of life-saving equipment and are not certified or approved for any kind of medical use. They are sold for novelty and entertainment purposes only.