Although they are designed as toy bases, we find that many birds use them as is, because the shapes are easy to grip, and they enjoy beaking and tonguing the many holes.
Circulo is 30mm diameter (about 1.5 inches). The 9.5mm centre hole is suitable for sisal rope, 1/4" veggie tanned leather lace, or stainless steel twist chain in sizes A or B. The 4 outer holes are 4.8mm; large enough for sisal or hemp twine, and 1/8" veggie tanned leather laces.
Baretta is 80mm long (about 3"), with 3 holes, each 6.4mm (about 1/4") diameter. The Baretta can be used with size A stainless steel twist chain, 1/4" stainless steel bolts, veggie tanned leather, hemp and sisal.
Sold in packages of 6.