Excalibur Crossbow X-Slick Rail Lube Blue. With an applicator that cleanly and evenly applies the oil the crossbow will deliver a smooth shot every time while preventing wear on the serving. Package Contents: Excalibur Crossbow X-Slick Rail Lube A silicon based oil packaged with a one of a kind applicator that takes the hassle and mess out of lubing the crossbow. With an applicator that cleanly and evenly applies the oil the crossbow will deliver a smooth shot every time while preventing wear on the serving.