Each "Sinfully Soft Cuff" is handmade with high quality leather and hardware (and suede for the purple "Sinfully Soft Cuffs"), to fit a great overall design, and provide a lifetime of use.
The main strap of each cuff is a double-layered, 1/8 inch thick, purple suede, which is soft but heavy to provide strength and rigidity to the cuff. The two layers are actually composed of one piece of suede, folded back over itself on both edges, and seamed down the center of the top, underneath the adjustable locking strap. I found this design to be quite nice, because it prevents any seams and sharp edges along the main cuff wherever it contacts the skin. Instead, the long edges of each cuff are now a smooth, rounded edge of suede, instead of a sharp cut. This main strap is glued between layers, and stitched the entire way around to finish it off. In total, this main cuff measures about 9" inches long, and 2" wide (actual measures do vary by about 1/16" plus or minus, because the cuffs are handmade).
Attached to this main inner strap, is the outer adjustable locking strap. This adjustable locking strap is solid 1/8" thick, 10oz. English Bridle Leather, so it's soft, thick, and SUPER strong; certainly built to last. The locking strap is 12 1/2" long, 1" wide, and attached to the main inner strap by 5 solid steel rivets, backed by nickel plated brass caps. Each locking strap has 5 different holes you can use to adjust the size of each cuff to accommodate wrists from about 4.5" to 8.5" in circumference.
Finally, the hardware continues to live up to the standard of quality set by the rest of the cuffs. Each cuff features a steel locking roller buckle, with a mirror nickel finish, and smooth movement. Each cuff also features a 1 1/4" nickel-plated steel d-ring, with welded seams, so once they are locked to something, there's no getting out.
As a further testimony to their quality Sinvention also provides a full lifetime warranty on every product they create! Bravo!
As a whole, Sinvention far exceeded my expectations with these "Sinfully Soft Cuffs." The design is great, the quality is superb, and the craftsmanship certainly follows suit. These cuffs have endured a few short play sessions already, as well as two extended lock-ups, and proved to be completely secure, and pretty comfortable for long-term use. After 2 months of use, I have only found one negative point that I can nit-pick on, and that is contact with the rivets. The nickel-plated side of the rivets sit exposed on the inside surface of the main strap, so when in use, they can come in contact with the skin. For the vast majority of the time, contact with the rivets is negligible to non-existent, but there have been one or two occasions when struggling against the restraints, when the metal rivet base made contact with the protruding bone (tip of the ulna) in my wrist, which is slightly uncomfortable, but alleviated immediately by shifting the cuff. As I said, a very minute issue.
Being constructed of leather and suede, it would be best to keep the "Sinfully Soft Cuffs" out of water. If soiled, the cuffs can be spot-cleaned with a damp rag, but for the life of the leather, avoid abrasive scrubbing, detergents, oils, and submersion in water. Personally, I find the best treatment for my leather gear is to use a natural beeswax treatment, periodically when needed. Additionally, it is best to store quality leather products out of direct sunlight, or heat-sources that may dry them out and cause cracking or deterioration.
I am quite picky with my leather gear and who I will purchase it from, but Sinvention has left me pleasantly surprised, and is now on the short list. I will certainly be looking to them in the future for more great hand-made, high quality leather products!