This will give the bird more variety when perching and will help exercise the feet and toes. By supplying an ample amount of perches of various sizes, although still small in diameter, the birds may choose whichever size is the most comfortable. Parrotlets love to strip the bark off of branches. Be sure to scrub it well and microwave it for 15 seconds at a time for one to two minutes. Keep an eye on it because it can catch on fire.
Untreated pine is nice because it is soft and they can chew it easily.
Perches made out of cement or covered with sand may be used for nail filing but only one should be installed in the cage at a time. Never wrap sandpaper around a perch to keep toenails from growing. They will not keep the nails trimmed but will only irritate the bird's feet and cause damage and disease. In the world of parrotlets, everything is a fun game. Parrotlets absolutely love to play.