# Sei Mio Complete Surrender Bondage Kit with Under-Bed Restraints

Under-Bed Restraints: Sei Mio Complete Surrender is a couples’ bondage kit built around an under-mattress tether and four cuffs, with sensory accessories and adult toys for different kinds of play. Its mix of restraint and standalone items offers variety, but users should agree boundaries, keep releases accessible and check cuff comfort during use.

- [Original product page](https://bargainpostbox.co.uk/product/sei-mio-complete-surrender-under-bed-restraints-kit)
- [View offer](https://bargainpostbox.co.uk/visit/sei-mio-complete-surrender-under-bed-restraints-kit)
- Market: UK
- Language: en-GB
- Currency: GBP
- Brand: Sei Mio
- Price: 66.99 GBP
- Previous price: 79.99 GBP
- Discount: 16%
- Price checked: 2026-11-14T10:08:25.694Z

Prices and deal status are the latest recorded data, not a guarantee of availability. Confirm the price and availability with the store.

## At a glance

- Under-mattress tether anchors four wrist and ankle cuffs at the bed corners.
- Cuffs are described as velvet-lined. The listing advises checking fit and circulation and ensuring prompt release.
- Blindfold and feather tickler are presented as sensory accessories that can be used separately.
- USB bullet vibrator, butt plug and play die round out the listed set.

## Pros

- The under-mattress tether avoids needing a separate bed attachment point, according to the listing.
- Several accessories can be used independently of the restraints, giving couples options beyond cuff-based play.
- The play die is included for taking turns choosing activities.

## Specifications

### Identity
- Brand: Sei Mio
- Manufacturer reference: SM-050
- Colour: Black
### Product details
- Package dimensions and weight: 36.4 x 19.3 x 8.5 cm; 690 g
- Country of origin: China

## Before you buy

- The listing describes the tether as fitting beneath a mattress but gives no mattress compatibility details. Check that your bed setup can accommodate it. Follow the listing’s guidance to agree a stop word or signal, keep cuff releases within reach, check circulation and stay with your partner.

## A good fit for

- Couples seeking a restraint kit with sensory accessories and separate adult toy options.
- Buyers whose bed and mattress arrangement can accommodate an under-mattress tether.

## Less suited to

- Anyone looking for a kit with stated cuff dimensions, tether adjustment range or confirmed compatibility with a specific bed setup. Those details are not provided.

## Frequently asked questions

### What accessories are described in the kit?
The listing identifies wrist and ankle cuffs, an adjustable blindfold, a feather tickler, a USB bullet vibrator, a butt plug and a play die, along with an under-mattress tether.
### How do the bed restraints attach?
The tether is described as sliding beneath the mattress, with a cuff brought to each corner. The listing does not specify mattress compatibility.
### Can the accessories be used without the restraints?
The listing says the blindfold, feather tickler, vibrator and butt plug can be used with or without the cuffs.
### What precautions does the listing recommend?
It advises agreeing a stop word or signal, keeping cuff releases within reach, checking cuff comfort and circulation, releasing promptly and staying with your partner.

## Alternative options

- [Amazon Basics Dusk to Dawn Night Lights, White, 2 Pack](https://bargainpostbox.co.uk/visit/sei-mio-complete-surrender-under-bed-restraints-kit)
- [Viners Assure Premium Paring Knife 3.5" / 9cm \| SaferTip Technology \| German Stainless Steel Blade \| Riveted Handle \| Fruit & Vegetable Preparation Knife \| Rounded, Blunt Tipped Blade](https://bargainpostbox.co.uk/visit/sei-mio-complete-surrender-under-bed-restraints-kit)
- [SEI MIO Doggedly Divine Doggie Style Positioning Strap, Padded Adult Toy \| An adjustable sex toy with a wide padded strap and handles, extending from 72 to 100 cm for partnered positioning play.](https://bargainpostbox.co.uk/visit/sei-mio-complete-surrender-under-bed-restraints-kit)
- [Viners Assure Stainless Steel Paring Knife 3.5" / 9cm \| SaferTip Technology \| Stainless Steel Blade \| Ergonomic Stainless Steel Handle \| Fruit & Vegetable Preparation Knife \| Rounded, Blunt Tipped Blade](https://bargainpostbox.co.uk/visit/sei-mio-complete-surrender-under-bed-restraints-kit)
- [Colgate Harry Potter Sonic Kids Toothbrush, Small Vibrating Head for Easy Access, Extra Soft Bristles for Gentle Cleaning, Easy On/Off Buttons, Slim Handle, AA Battery Included](https://bargainpostbox.co.uk/visit/sei-mio-complete-surrender-under-bed-restraints-kit)
- [JAYU PET Dental Care Brush \(Soft Bristles\) 1ea - Dog Toothbrush, Cat Toothbrush, Dental Care for Kitten and Small Dogs, Removing Old Plaque and Tartar, Cat Teeth Brushing & Easy Cleaning](https://bargainpostbox.co.uk/visit/sei-mio-complete-surrender-under-bed-restraints-kit)

## Images

![Sei Mio Complete Surrender Bondage Kit with Under-Bed Restraints — 1](https://bargainpostbox.co.uk/i/i5avtpUclRvOAiuJsc9kHY_7wFNsGPuJ1VGxMcOyC8OnHDG_o4i07r-6pOfRJX9A48CI3n6CLZDVdplESKLThKcv6UJKms8w4AiD9rwvTafHmWllzkhWf1vc.jpg)