I Remixed Devongb's design to fit the R36S as i loved the grip feel in the hands and could not find a better designed grip for it that was available for free

If you like the Xbox 360 controller feel you will love this!

I removed the USB bottom cut-out so no charging or headphone access while grip in use, found it more durable without the cut-outs.

I used a Self Adhesive Sticky Back Multipurpose Felt Sheet cut into 2.5 x 1.9 cm and stuck it to the inside of the grip for a snug fit. [1.75mm Felt thickness] (You can find these sheets on amazon or ebay as furniture protectors, make sure the sheet is between 1.5 - 2mm thickness and cut it to your desired size)

[1.5mm Felt thickness] looser fit

[1.75mm Felt thickness] medium fit

[2mm Felt thickness] tight fit