Product information Size:Twin. Additional Information. Try. Account & Lists Account Returns & Orders. The Mainstays 9" White Jacquard Smart Box Spring sets up in seconds with no tools required and is available in Twin, Twin XL, Full, Queen, King, and California King sizes to create the perfect sleeping platform in any bedroom. The Mainstays 9" White Jacquard Smart Box Spring sets up in seconds with no tools required and is available in Twin, Twin XL, Full, Queen, King, and California King sizes to create the perfect sleeping platform in any bedroom. The Mainstays 7" White Jacquard Smart Box Spring sets up in seconds with no tools required and is available in Twin, Twin XL, Full, Queen, King, and California King sizes to create the perfect sleeping platform in any bedroom. Product information Size:Queen: 79.00 x 59.50 x 5.00 Inches. The Mainstays 5" White Jacquard Smart Box Spring sets up in seconds and is available in Twin, Twin XL, Full, Queen, King, and California King sizes to create the perfect sleeping platform in any bedroom. The Mainstays 9" White Jacquard Smart Box Spring sets up in seconds and is available in Twin, Twin XL, Full, Queen, King, and California King sizes to create the perfect sleeping platform in any bedroom. Home & Kitchen Hello, Sign in. Additional Information. ASIN B084WRJ27N Customer Reviews: 4.6 out of 5 stars 79 ratings. Skip to main content.ca. ASIN B084WGQDV1 Customer Reviews : 3.5 out of 5 stars 3 ratings. The Mainstays 5" White Jacquard Smart Box Spring sets up in seconds and is available in Twin, Twin XL, Full, Queen, King, and California King sizes to create the perfect sleeping platform in any bedroom. The Mainstays 5" White Jacquard Smart Box Spring sets up in seconds with no tools required and is available in Twin, Twin XL, Full, Queen, King, and California King sizes to create the perfect sleeping platform in any bedroom. ASIN B084WSHGY4 Customer Reviews : 4.4 out of 5 stars 11 ratings. Prime. Product information Size:Twin. This innovative box spring is designed to easily fold up for convenient storage and transport when not in use. Additional Information. Spring Mainstays 5" Easy Assembly Smart Box (Twin-XL): Amazon.ca: Home & Kitchen. Set yourself up for a great night's sleep with the Mainstays 9" White Jacquard Smart Box Spring.