This is a red insulated binding post. These binding posts *do* accept banana plugs, and are a great way to connect single-wire leads. The colored cap screw
Binding Post Connector Standard Fluted Black
CL159709
WBT's Crimping method is the preferred technique because it produces a physically and chemically optimum contact point with low transition resistance,
WBT 0765R Midline Fully Insulated Binding Post Banana Jack Red
SparkFun Education - Kits and Materials - SparkFun Redboard
Binding Posts — Parts Connexion
9412 - E-Z-Hook, A Division of Tektest, Inc.
Binding Post - Red from MindKits New Zealand
14.4v Rechargable Battery Power Supply ^updated With Banana
Binding Post - Red - PRT-09739 - SparkFun Electronics
Binding Post – Electronix Express
Description Features These are various leaded cables for attaching to multimeters, power supplies, oscilloscopes, function generators, etc. Cables
Banana to IC Hook Cables
7004 Keystone Electronics, Connectors, Interconnects
WBT's Crimping method is the preferred technique because it produces a physically and chemically optimum contact point with low transition resistance,
WBT 0765R Midline Fully Insulated Binding Post Banana Jack Red