When I purchased the Clear Prop 1/144 Ki-51 set a while back, I thought to myself that there was no way I'd be able to locate a set of masks for the canopy on this aircraft. The canopy is seriously small, but not being able to mask it would have the model looking a bit toy-like.
Fortunately, a company called Dead Design in the Czech Republic has been specializing in Japanese WWII aircraft mask sets, and it includes one for various 1/144 kits. This includes the Clear Prop Sonia.
So, I found a US retailer that carried some of their masks and one was this set for the Ki-51. The masks are on a section that measures only 3 x 3 cm. Not only that, but there are two sets on this. Even with a 10x loupe I had difficulty seeing the the demarcations on the tiny sheet. But they are there and when I get around to the kit, I'll definitely be giving this one a go. The set comes with a full placement guide that is quite well done and will be very useful. Fortunately, I have a pair of very small point tweezers that will be required for this set.